Search Documents

By Thomas R

The successful `marriage' between a company seeking to raise funds to develop a project and their financiers calls for a strong mutual understanding of each other's needs. For a company attempting to raise funding, the alternative methods are ever expanding. The optimum method will vary depending on the financial position, risk/reward outlook of the company and the strength of the project for which development capital is being sought. It is likely that small mining companies will need to raise equity funds for advancing projects to the development stage. At that time, they will probably still require a reasonable level of shareholder equity to meet the requirements of banks and other parties to cover potential cost over-runs on the project and feasibility costs. Larger companies, however, are likely to find it much easier and cheaper to raise debt from banks. When evaluating companies and projects for funding, banks will pay particular attention to the quality and experience of management in developing similar projects and it may be necessary for some companies to retain the services of outside consultants. Before a project needs funding, companies should meet with potential financiers to develop relationships to select and ensure a smooth transaction to funding in the future.

Jan 1, 1997

By Jancar T, de Guzman M M, Matthews B, Tu J. Y

The use of computational simulation to predict the performance of existing equipment or for the design of improved mineral processing equipment will be referred to as Computational Mineral Processing (CMP) in this paper. The emphasis will be on solving the governing equations for liquid solid flows in complex geometric domains to obtain, typically, the three-dimensional distributions of velocity and pressure for the liquid phase and the velocity and concentration for the solid phase. The underlying technology, computational fluid dynamics (CFD), is very well-developed in other industries (aircraft, car and chemical) and forms a vital part of product design and analysis. The subsequent design of improved mineral processing equipment may also involve finite element structural analysis (FESA). Computational fluid dynamics (CFD) and finite element structural analysis (FESA) are part of the generic discipline of Computational Engineering and Science (CES). Ciment and Scherlis (1993) define CES as `The systematic application of computing systems and computational solution techniques to mathematical models formulated to describe and simulate phenomena of scientific and engineering interest'. Increasing computer power (Kaufmann and Smarr, 1993), is a dominant factor determining the rapid growth of industrial utilisation of CES. This increase is happening at both the supercomputer and the workstation level. Indeed, today's typical workstation, a Hewlett-Packard 735, is as powerful as a CDC 7600, the leading supercomputer in 1970. Future computer architectures are expected to become increasingly parallel (Gartner Group, 1990) allowing a sustained performance of a teraflop (a million megaflops) to be achieved well before the Sydney Olympics in the year 2000. It is recognised that the modem development of most disciplines in the physical sciences rests on the three complementary strategies of experimentation, analysis and computational simulation. As the 21st century is approached the volume of computational simulation, both fundamental and applied, is growing dramatically and the role of experimentation is diminishing. In the area of equipment design, CES provides the following advantages over experimental testing and measurement: 1. lead time in design and development is significantly reduced; 2. CES can simulate conditions not reproducible in experimental tests; 3. CES provides detailed and comprehensive information; and 4. CES is more cost-effective and time-efficient. The ultimate benefit for industry is greater productivity and hence greater profitability. The broader issues in relation to CFD are discussed by Fletcher (1993b). In the five- to ten-year time frame, growth in computer power will make it practical to combine CFD and FESA with optimisation procedures to produce a design process that is almost fully computerised. It is expected that fully automatic

Jan 1, 1995

The provision of electrical power is an important consideration in project develop- ment. The first step to be taken in this area is to assess the power requirements of the project. The alternatives of taking a supply from a power authority or providing local generation can then be considered. This requires additional definition of the prob- able characteristics of the supply. The availability of authority power in Australia is limited by the extent of the state power grids. Recent developments now allow these grids to be extended and their load capacity increased to meet major load increases at less cost than was possible pre- viously. The options for local generation include diesel, gas turbine, steam, hydro, solar and wind, each having its particular performance characteristics and costs. The choice of fuel for diesel, gas turbine, and steam plant likewise involves consideration of a range of factors. The arrangements adopted for a number of development projects illustrate some of the aspects which influence the decisions on power supply.

Jan 1, 1986

Computers are playing an increasing role in the management of technical data in mines. Companies are re-assessing the role of their data processing departments as users demand computer resources in non-accounting areas. Data of all kinds is now being seen as a, company resource, and the role of computing professionals is to help to manage the data flow, not merely to manage computers. The concept of distributed data bases puts the responsibility for data entry, editing and updating with the user. This challenges conservative views of centralized control of computing, suggesting, instead, centralized co-ordination. A survey of the possible applications of computers in technical areas points up the special requirements of handling raw, processed and consolidated technical data. Technical data bases have become flexible as mini- computer hardware and software have rapidly developed. Management has the ultimate responsibility for efficiently administering corporate data bases, and it must ensure suitable policies are developed for this purpose, with enough flexibility to cope with the impact of fast changing technology.

Jan 1, 1980

By X Xia2, X Wang, G Liang, T Song, F Ma

Inertia cone crushers have found applications mostly in steel slag crushing operations in China. Compared with conventional eccentric cone crushers, the crusher has an obvious advantage in reducing product size. In addition, they are mostly used in two-stage open circuit crushing flow sheet, which simplifies the crushing process. However, inertia cone crushers are not widely used in the mineral processing industry due to their low crushing capacity. In this paper, the throughput performance of the inertia cone crusher was investigated in a laboratory-scale inertia cone crusher and relationships between operational parameters were identified. Iron ore was crushed using orthogonal experimental method under different machine parameters and operational conditions. The crusher throughput and product size distributions were determined. The effects of parameters such as eccentric speed, discharge gap, eccentric mass and eccentric distance on product mass flow and product size were investigated. The results of this study can help reduce the feed size of the mill in order to reduce total energy consumption of comminution.

Aug 24, 2022

Diversification has characterised the mining industry in this country and globally in recent decades, and in Western Australia in particular. One of the most obvious aspects of diversification is technological change which continues at a rapid and sometimes bewildering pace. A function of technological advances is the increased capacity to further diversify the range of minerals which can be identified in economic concentrations and profitably extracted. This broadening of the total base of the industry has a synergistic effect on its further development by extending its geographical spread and increasing scope for decentralised infrastructure. Another aspect of diversification is the corporate thrust towards establishing overseas mining bases for a variety of reasons. Off-shore (sea bed) mining is a further manifestation of increasing diversity, although very much in its infancy.

Jan 1, 1996

By Shuqing L

The application of single liquid cement for fracture grouting in base rock may have history more than 120 years. The disadvantage of it is difficult to increase the grouting efficiency, because the jelling time of it is very long and hard to control. The double liquid grout, such as chemical grouts and cement water glass grout was developed at the end of 1960.'s Although the jelling time of this kind of grout can be controlled, it mast adopt double liquid grouting technology, use complicated equipment and is not easy to control component's ratio of the grout. Another disadvantage for chemical grout is high price, and have pollution to environment. OCE series single liquid grout is the effective grout material developed recently by making large efforts in Ohina. Main feature of it is that the jelling time is easy to control, materials from cement and clay are very cheap and without pollution to environment, and the grout can be injected by single liquid technology. The effect of QCE series grout has been proven by its application in China. It can be believed that QCE grout has great economic efficiency and will give a push to develop grout material.

Jan 1, 1988

By Sroka J

A comprehensive feasibility study should be submitted as part of the loan application to a financial institution for debt funding of a proposed project. Its scope should include technical, costing, marketing and other aspects pertinent to the project. The technical presentation should be sufficiently detailed to show that the assumpt- ions concerning future performance are realistic. A lender needs to be convinced that the capital and operating cost estimates are conservatively based with adequate allowances included for contingency and escalation. The marketing assumptions determine the level of revenue from which operating cost, debt servicing, and other commitments are to be met. The foregoing aspects establish the economic viability of the project, and are therefore relevant to the risk assessment and cash flow analysis carried out by a potential lender which determine his ultimate lending Decision

Jan 1, 1978

Because the Australian resource industry differs from the resource industries of other countries, direct application of manpower planning processes derived from overseas experience may be singularly inappropriate for Australian projects. Too often in Australia, project manpower planning has been undertaken as an afterthought to technical and financial analysis. A wide variety of complex and interrelated manpower considerations should be evaluated from the beginning of project planning, even at feasibility study stage, and relevant deductions should be incorporated into all other planning. Many manpower factors can be considered sequentially but it is probably necessary to undertake critical path analysis for manpower planning. The paper highlights some key factors involved in project manpower planning and suggests a simple linear planning sequence which integrates the analysis of factors and can in turn be integrated into technical and financial planning.

Jan 1, 1983

By Gleadow AJW, Foster DA, Kohn BP, Raza A

A large and increasing data base of apatite fission track results from sedimentary and granitic rocks exposed within the southeastern highlands and along the continental margin of Australia provides constraints for the tectonic development of the southeastern passive margin. The fission track results suggest that many regions of the southeastern margin of Australia experienced distinct episodes of relatively rapid cooling during the middle Cretaceous to early Tertiary that can be attributed to the effects of rifting. One cooling episode is middle Cretaceous in age and related to denudation of the southeastern highlands from Tasmania to northern New South Wales between -90-100 Ma. Rocks exposed along the present coast line record a later episode of rapid cooling, which is diachronous and decreases in age northward from -80 to 90 Ma in northern Tasmania to southern New South Wales, -60-80 Ma in central and northern New South Wales, and to -50-60 Ma in southern Queensland.

Jan 1, 1995

The paper explains the genesis of the Ballarat College of Advanced Education to its unique position in mining engineering education. A description follows of the development of the Graduate Diploma in Occupational Hazard Management which commenced in 1979 in the cooperative mode of four groups of three weeks full- time study followed by twenty-three weeks in industry. In particular an analysis will be given of the state of origin of students, ages and employing industries. Given the experience from the evolution of this course a similar process is described for the Graduate Diploma in Mining which has been accredited to commence early in 1987.

Jan 1, 1986

The integration of economic, cultural, social and environmental decision-making has increasingly become globally recognised as the only acceptable way of doing business consistent with sustainable development. This concept requires a move to a new economy, where environmental, cultural and social issues are accounted for and integrated in business decisions and practice. There has been much discussion on sustainability and sustainable development, but organisations are still grappling with what this means in reality for their business and how they should respond. The challenge is to take the way we do business to a new paradigm and make solutions relevant to business. This paper will look at some of the strategies and programs being adopted or considered by resource companies as they move towards a more sustainable future. These include defining a sustainability framework for their organisation, developing the business case and planning approach. Also included is a brief overview of some of the new approaches to environmental management, such as reducing materials and energy intensity, minimising or eliminating impacts through better waste and emissions management and process control, taking a whole of life approach to products and conserving resources. The concepts of Product Stewardship, Eco-efficiency and Cleaner Production will all be discussed.

Jan 1, 2002

By S Cossfo Torres

Minera PenmontÆs gold mine, La Herradura, is located at the northwestern Mexican state of Sonora and consists of an open pit mine and heap leaching facility for the recovery of gold. The production began in July 1998, and today La Herradura produces about 200 000 oz of gold per year. Standard sampling and assaying protocols were established during exploration based on heterogeneity tests. However, at deeper zones of the pit, coarse gold became evident and it was necessary to develop a new sampling protocol in order to minimise the fundamental error and improve the metallurgical accounting. This new sampling protocol requires cyanide leaching the whole pulverised sample from the blasthole, assaying pregnant solution and fire assaying 50 g of tailings. A sampling study was performed on 195 blasthole samples analysing gold under the standard and new protocols. The new protocol demonstrated that the original one underestimated gold grade by approximately 27 per cent, with impacts on ore misclassification and metallurgical accounting. According to the ore grade control system, mineral with gold grade above 0.35 g/t was sent to the leach pad and mineral with lower grade was classified as waste. Based on the sampling study, it was decided to classify a low-grade ore with gold assay between 0.20 and 0.35 g/t which was stored for future treatment under better gold prices or should mine production decrease. These two conditions were present during 2005 and 2006, when about 3.5 Mt of low-grade ore were leached.

Jan 1, 2008

Gekko Systems Pty Ltd have developed the Python Underground Processing Plant for the concentration of gold and sulfide ores. The Python plant has an established flow sheet including fine crushing, screening, gravity separation and flotation which aims to concentrate the valuable minerals (gold/sulfides). The aim of the plant is to achieve high valuable recovery into a mass yield of 10 - 30 per cent to reduce the amount of material that is needed to be taken to downstream processing. This paper examines the test work protocol for testing an ore to assess its suitability for the Python flow sheet. This paper will discuss the test methods employed to determine crushing requirements, continuous gravity recovery and flotation performance and how the results relate to Python design for the comminution, gravity and flotation circuits. Results from past test work will be discussed.

Aug 1, 2010

By Z-Y Pi, B Zhang, S Wen

"The paper introduces the structure and work processes of outside auger hollow claw tipped mechanical sampler for coal. Twenty sets of claw tipped sampler performance tests show that: The design of inner hollow cylinder-type (?180 mm) can ensure to take a coal sample with nominal top size of 60 mm. Built-in self-cleaning piston pusher ensures no adherence and blocking of the sample. The operation practices show that the mechanical sampler can operate in order for taking coal sample with up to 16 per cent of total moisture. Claw closing design can avoid sample leaking or spilling during the claw lifting and ensure the integrity of primary increment. Ultrasonic positioning device makes the sampler capture the materials no less than 10 cm from the bottom of the wagons, basically meeting the requirement taking full depth of the sample. The precision and bias test indicates that the moisture and ash have no relative bias under the sampling process; the sampling precision is in accordance with the requirement in IS013909.At present, the spiral mechanical sampler is widely used for coal sampling but there are many limitations during application, for example: It is difficult to capture a large size sample, so the size range of a coal sample taken is limited. There is easy adhering or blocking for high moisture coal, which will result in the mixture of different increments, wear of sampler and the difficulties for cleaning and maintenance of sampler. It is difficult to capture the coal sample at lower than 30 cm from the bottom of the wagons, in order to avoid damage of the vehicle. It is possible for coal sample loss and spilling during the sampler lifting, due to the unsealed sampler.For the outside auger hollow claw tipped mechanical sampler designed for solving the above problems, the opening distance of the claw is the opening size of the sampler and makes the size range of the coal sample to be taken wide. During sampling, the two pieces of claws open and the sampler rotates vertically downward to capture an adequate coal sample after reaching the specific point. Then the two pieces of claws close tight automatically to ensure there is no coal leaking or spilling. The inner pusher of the sampler will prevent from the adherence and blocking of the coal sample effectively.CITATION:Zhang, B, Pi, Z-Y and Wen, S, 2012. Outside auger hollow claw tipped mechanical sampler for coal, in Proceedings Sampling 2012, pp 41-44 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 21, 2012

By C E. Woolley, A Hosseini, J Foster

Northern Star’s Thunderbox Open Pit C-Zone cutback was designed to maximise extraction in a short life excavation; In fresh rock on the western wall this included 20 m to 30 m bench heights with 6.5 m to 10 m berm widths and a 90° pre-split angle. Rock mass quality in this area is generally fair to good, however, there are sections where the dominant foliation runs parallel with the designed pit wall, and more closely spaced, altered, foliation is present: these areas are difficult to predict and prone to failure. Stringent controls and monitoring were required in order to safely access below these areas, in particular the use of slope stability monitoring radar, Trigger Action Response Plans (TARPs), re-entry procedures, visual inspections, drone inspections and day-to-day personnel awareness of the hazard. Robust and comprehensively planned remediation was also required after two significant slope failure events where long reach equipment and rope access techniques were utilised to remediate the areas in question safely, but also in a timely manner, such that expected production targets were impacted as little as reasonably practicable. This combination of rigorous risk management and well planned remediation resulted in a successful and complete extraction of the C-Zone cutback with no impact to operational safety.

Jun 22, 2022

Preparing for automated sample preparation has two facets; the need for better procedures as seen by the laboratory Manager and the approach to be adopted as envisaged by the equipment manufacturer. Both have many options and during the 1990s some at least of these options will be tried. As automation of sample preparation is only just beginning, can it be said that there is a real need for better procedures. What does automated sample preparation have to offer? Does it have real advantages or is it just a marketing tool to sell equipment?

Jan 1, 1976

Mr. P. F. THOMPSON said this matter was one of very great importance to producers of lead. His association with the matter was that he happened to be the Institute representative on the Committee of the Standards Association of Australia charged with formulating a standard for chemical lead, that is, lead used in technical chemistry for acid chambers and the like. The British standard had this test incorporated in it, but those on the committee felt that it should not be included in the specification. The main objection was that in an accelerated corrosion test one was endeavouring to do in a few seconds what in natural conditions would take years; and it was now being recognised that such tests were of little value in assessing the corrosive properties of a metal.The flash point test was carried out with boiling hot strong sulphuric acid; but no chemical manufacturer would be likely to use such in contact with lead. There were many factors such as the formation of steam, the chemical reduction of sulphuric acid, the evolution of hydrogen, the catalytic effect of the surface lead, affecting this test, other than the presence of the segregated impurities upon which this test throws the onus of the whole imperfection of the lead. Mr. Russell had shown that lead which had stood the test of time often gave a low flash point. They were endeavouring to find rapid methods of estimating minute amounts of the more important impurities, which would eliminate the labour and expense of a full analysis.Mr. H. St. J. SOMERSET thanked Mr. Thompson for his remarks. He supposed some of those present knew that the Broken Hill Associated Smelters was responsible for Mr. Russell's investigations at the University, and he could only agree with Mr. Thompson that the flash point test, which had been accepted at the present time...

Jan 1, 1930

By Partridge AC

The measurement of particle size is very important in many industries. Comments in this paper refer principally to the Mineral Industry and in particular to Coal Mining and Coal Preparation. The objective is to indicate the importance of particle size in process design and process assessment and to describe techniques for particle size measurement and the presentation of results.

Jan 1, 1984

By Smith T. N, Wild M. B, Elliot B. J

The process of flash smelting of nickel sulphide ores, as practised at the Kalgoorlie Nickel Smelter, is described. The critical variables in the operation of this process are identified. The design of a pilot-scale, turbulent-jet flash reactor which models the essential features of the industrial smelter is described. A report of its operation and application to an investigation of the ignition of particles of sulphide species is given.

Jan 1, 1991