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By Watt KL

Chemical anchors for use in rock bolting have been produced in Australia under licence for several years. These anchors are alternatives to the more normally used mechanical anchors and give improved anchorage strengths under some conditions, although at greater cost. Considerable development during this time has resulted in an improved sausage-type chemical anchor more competitive in price, to such an extent that its use is increasing markedly. Particular-improvements allow load application up to the strength of the bolt within 2 min, reduction in cost, self-extinguishing features in the resin, improvements in manufacturing techniques, and an improved water- insensitive casing. At the same time, smaller bolt sizes have allowed reduction in resin volumes with consequent cost reduction. At this stage several aspects remain to be improved, particularly specialty anchors for specific purposes and Packaging.

Jan 1, 1971

For many crushed aggregate producers will the finest fraction minus 4 mm represent a problem. The fine material will fetch a much lower price than the coarser products, and may even be difficult to sell in some markets. The blasting operation will strongly influence the generation of fines after both blasting and crushing. Drill hole deviation together with the drill hole diameter, powder factor and velocity of detonation are the most important blasting parameters with regard to the generation of fines. Drill hole deviation is often ignored, and many operators will just reduce the drilling pattern in order to avoid hard bottom and an excessive number of boulders. The paper presents a technical and economic analysis of how drill hole deviation will lead to an increased generation of fines in crushed aggregate production. The analysis shows that the loss of sales revenues will be much higher than the extra costs for drilling and blasting caused by compensating for drill hole deviation by putting in more holes.

Jan 1, 1999

A continuing demand for exploration geologists, at a level well below that during the mineral "boom" of 1967-1971, will be highly selective. The exploration geologist must be more than the traditional geologist whose primary function has been detailed description of rocks and their recording on a geological map. He must be capable of 1. reconnaissance recognition of favour= able environments for ore mineral concentrations, 2. application and interpretation of techniques of search and evaluation, and 3. evaluation of economic, technological and political interactions that combine to make an ore deposit. Universities have an obligation to their students to provide them with a saleable skill, to educate them so that they can cope profess- ionally and socially, and to provide a mechan- ism by which education can be a continuing process. Humanistic and social studies, develop ment of communication skills, understanding of economic and management principles, ability to assess rock properties that influence extract- ion and beneficiation, and a knowledge of technological developments and limitations are necessary parts of the exploration geologist's

Jan 1, 1974

Infrastructure is defined as all those parts of a mining development which are not directly concerned with mining and mineral processing. Infrastructure is of significant and growing importance in the overall develop- ment of mines, and the costs could be critical in determining the viability of a project. Prior to_project authorisation, feasibility studies are required, often in considerable detail, to determine costs with adequate reliability. It is necessary that the Engineer should be adequately briefed for carrying out these studies and that good liaison and communication with the Owner be maintained. Methods, costs, order of accuracy, and some special requirements of these studies are discussed. After project authorisation, rapid im- plementation of the proposals is generally desired. A suggested organisation and method for this implementation is presented and dis- cussed. Comments on fees, and particular points in the relationship between Owner and Consulting Engineer are given. Particular reference is made to differences in conditions compared with public works projects. Realistic attitudes of mind towards environmental matters, industrial relations, and contractual relationships are advocated.

Jan 1, 1974

The reality is that in today's world almost half of nearly six billion people on the planet do not have access to commercial energy and the services it brings. Based on UN projections, in 30 years time there are likely to be nearly three billion more people in the world, over 90 per cent of them in countries which are already economically poor. The World Energy Council (WEC), through its 102 member countries, monitors trends and developments and projects future trends. WEC is a non-governmental international body representing all forms of energy and is committed to the sustainable use of energy for all mankind. This paper is based on WEC studies and papers presented at its many conferences and congresses worldwide. Primary energy demand growth is dominated by the developing countries over the next 30 years. The world energy mix is projected to change very little over the next 30 years. Fossil fuel supplies (ie coal, oil and gas) are likely to decline from 77 per cent to 73 per cent, nuclear energy may grow from five per cent to six per cent and renewable energy sources (eg hydro, solar, geothermal, wind, tidal and biomass) could increase from 18 per cent to 21 per cent. World energy consumption is expected to grow by over 50 per cent over the next 30 years. The paper reviews changes in energy demand in the world, particularly in the Asia/Pacific region. Environmental issues are covered, as are developments such as solar energy from space and the status of renewable energy forms. Agendas for action to achieve change are also reviewed.

Jan 1, 1997

BHP Billiton Mitsubishi Alliance, or BMA, is AustraliaÆs largest coal miner and exporter, and is currently responsible for around a quarter of AustraliaÆs total annual coal exports. BMA and its predecessors have been part of the Queensland mining scene for around 40 years, developing world-class mines, a port, overseas markets, and an international reputation for quality and reliability. From its production base in QueenslandÆs Bowen Basin, BMA produces a broad suite of coals which are supplied to 73 customers in 24 countries. BMA was formed in June 2001 as a partnership between BHP Billiton and Mitsubishi Development Pty Ltd, under which the two companies share equal ownership and management of eight Central Queensland coal mines û Goonyella Riverside, Broadmeadow, Peak Downs, Saraji, Norwich Park, Gregory, Crinum and Blackwater û and the Hay Point coal export terminal near Mackay. This case study focuses on Peak Downs Mine, which was the second largest open cut mining operation to be developed in the northern Bowen Basin for the original CQCA Joint Venture. The first coal was mined in April 1972 and today, Peak Downs has a production capacity of over nine million tonnes of coking coal per annum. The mine is located 30 km south of Moranbah and 195 km south west of the Hay Point port facilities. Coal is mined by open cut mining methods using six draglines and two truck/shovel stripping fleets for overburden removal. Coal seams are mined using excavators and front-end loaders and 210 tonne capacity coal haulers.

Jan 1, 2007

By Kuzugundenli OE, Nagaraj DR

Organic complexing agents have received special attention over the past few decades in the search for reagents for improved flotation separation of minerals, especially non-sulphides. The majority of such reagents that have been proposed over the past few decades have remained largely a laboratory curiosity, except perhaps alkyl hydroxamates, because their selection is seldom based on commercial viability. In this regard, the choice of complexing agents such as oximes may be more realistic because of their widespread use in solvent extraction of copper. Our earlier studies have confirmed that they are also effective as collectors for copper oxide minerals, including chrysocolla which is the most difficult copper mineral to beneficiate. The flotation behaviour of chrysocolla for several structurally-related hydroxyoximes were studied as a function of pH and oxime concentration and the role of structural features examined. The structural changes studied included substitutions in both chelating and non-chelating parts of the molecule. The results indicated that, contrary to expectations, many of the structural changes in the basic molecule, salicylaldoxime, do not have a positive effect on collector efficiency. The reduction in collector efficiency is rationalised on the basis of possible steric factors affecting complexation and packing of the collector species on the mineral surface as well as effects due to changes in electron density brought about by substituents. Introduction of alkyl substituents on the oximic carbon of salicylaldoxime yielded the highest collector efficiency.

Jan 1, 1993

Environmental management of minesites in general, and management of water discharges in particular, is receiving ever-increasing attention. One key component in the successful design and operation of water management systems is to address the presence of sediment in the water being conveyed. Sediment erosion in the mining environment is often greatly exacerbated by disturbing the ground surface of vast areas of catchment. If sediment avoidance, transport, deposition or release are not adequately addressed, the impact on water management facilities can include loss of storage and hydraulic capacity, more frequent equipment replacement, increased operational costs and potentially environmentally unacceptable sediment discharges to receiving waters. An overview of sediment management within water facilities is presented here, and design of one particular approach, the use of settling basins for sediment removal, is discussed in detail. Examples are used to illustrate lessons learnt where particular approaches to sediment management have been found to be lacking. The common themes in the lessons learnt include the need to characterise hydrodynamic conditions and sediment properties in the water source, to set performance targets for sediment management, and to develop operating procedures to meet these targets under a realistic range of scenarios. The examples show how analysis of expected performance of sediment management can help with planning of operation and maintenance strategies. For settling basins, use of a simulation model that includes the effects of turbulence on settling can provide considerable benefits in optimising basin design and evaluating performance. Even in the most basic approach to sediment settling, establishing performance targets based on design flow and sediment characteristics is critical.

Jan 1, 2003

By F F. Pitard

Observation from attending many conferences around the world reveals that many people are constantly shifting from the word ‘error’ to the word ‘uncertainty’ without a clear vision of what the subtle difference is. The same applies to a large swath of the scientific literature, in which these two concepts are unfortunately often used synonymously, which is a scientific flaw of the first order. In practice, as demonstrated in the Theory of Sampling (TOS), there are both sampling errors and sampling uncertainties. Sampling errors can easily be preventively minimised, while sampling uncertainty for a preselected sampling protocol is inevitable. P M Gy’s work, supported by G Matheron’s critical reviews, demonstrates beyond any possible doubt that sampling uncertainty cannot be achieved if sampling errors are not preventively minimised by applying very stringent rules that are too often ignored by sampling practitioners. A clarification, in line with the TOS, is presented to mitigate the confusion created by circles favouring the use of uncertainty versus the use of the word error. Both words are very different in nature and scope and they are both necessary in their due place and time.CITATION:Pitard, F F, 2017. From errors to uncertainty – a clarification for proper use by the Theory of Sampling, in Proceedings Eighth World Conference on Sampling and Blending , pp 355–358 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

By Runge IC

The mine planning process is reviewed and appropriate software considered in terms of "line process" or "support function". The mine planner's requirements of a geological model and the elements of and requirements of a computerised mine planning system are all discussed. The use of "support" software for mine planning is considered and general rules for its development are given. Important changes involved in implementing a computerised mine planning program are listed.

Jan 1, 1983

For several decades miners have been obliged to maintain a vast supply of sharp steels at the working face to meet the hungry needs of rock-drills. In medium and large size mines this has meant the setting up of an organisation to store steels, to make and sharpen bits with all the complication and skill of forging, hot milling and heat treatment, and to transport sharp and dulled steels to and from the working face with all its labour, wastage, and inconvenience to other mining operations.In a mine with 250 rock-drills in use, a flow of more than 60,000 sharpened steels each month has to be maintained to keep the machines fully employed, so some idea of the magnitude of this problem may be grasped.For a long time it has been apparent that it is mainly the bit itself that wears, and many attempts have been made to reduce the enormity of the problem by providing detachable steel bits which could either be used once and rejected, or sharpened three or four times before rejection.At the same time metallurgists have striven to 'improve the quality of the steel and the heat treatment afforded it so that a bit, readily workable In a normal mine drill-shop, could be produced having a high resistance to wear and fatigue; but, although various alloy steels have been marketed, it is still usual to find many mines relying on a "straight" carbon (0.6 - 0.9% C.) steel for their drill steels.Since 1915 increasing use has been made of tungstencarbide as a cutting implement in the engineering industry. Where, on account of its great hardness and long life, it...

Jan 1, 1948

By AUIMM AUIMM

Continuous Improvement The Council of the AusIMM should expedite the introduction of a continuous professional education policy along the lines of that to be proposed to you by David Pollard today. The Education and Accreditation Committee must continually review the training needs of the next generations of mining industry professionals. It should continue to demand and encourage the creation of the schools for the training of such people. The AusIMM could even put greater onus upon university researchers to accredit university post graduate degrees.

Jan 1, 1994

By Jin C, Shi X

The electrochemistry of leaching gold with thiosulphate has been studied systematically by using electrochemical techniques. Results show that the current peak of anodic dissolution of gold occurs at about 50 mV(SCE) and there is passivation in the polarisation curve in the thiosulphate solution in the absence of ammonia. Ammonia markedly improves the anodic dissolution rate of gold and reduces the passivation as well as making the current peak shift negatively. Results also show that there is no current peak for a cathodic process in the range of 0 -900 mV(SCE) in the thiosulphate solution in the presence of oxygen but absence of cupric ions and ammonia. In the solution containing 0. 1 mol/L cupric-ammonia ions, the peak occurs at about -400 mV (SCE) and the cathodic process is characteristic of a catalytic reaction. Oxygen presents a predominate effect on the cathodic process. Based on the electrochemical investigation, the following mechanism of leaching gold with ammoniacal thiosulphate has been proposed. Ammonia reacts primarily with gold ions on th anodic surface of gold and the formed A (NH3)2+ rea~s then with S2O 3 in solution to form the stabler Au(S203) 2 . Cu (NHS) 4 gains electrons on the cathodic surface and is reduced to CU(N) ? which is then oxidised by oxygen and regenerated into Cu(NH3) 4 after entering the solution.

Jan 1, 1993

By Brouwer G, Shaw J

As South African gold mines go deeper, and improved and more uniform working condi- tions are required, ever larger amounts of refrigeration are needed. At the same time new and more suitable cooling equipment is becoming available for use with new mining layouts as well as on existing shaft systems. The advent of the large diameter rotor screw compressor has meant that there is now a machine available with great flexibility in performance and construction for efficient underground use. The first installation using this type of machine is described.

Jan 1, 1988

By C Riley, N Davies, J Carpenter, I Lipton

Nautilus Minerals Incorporated (Nautilus) recently announced the worldÆs first Seafloor Massive Sulfide Mineral Resource at Solwara 1 in the Bismarck Sea, Papua New Guinea . The discovery, exploration and resource modelling of this æblack smokerÆ system located 1500 m under the sea involved unique technological development. Whilst the resource estimation methodology had similarities with approaches adopted for analogous volcanic-hosted massive sulfide (VHMS) deposits, specific parts of the resource estimate called for new ways of assessing data. This paper discusses several innovative methods for collecting and assessing Solwara 1 exploration data. This ia an ABSTRACT only. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By E Hernandez, I Agustian, W Kusumohastuti

PT Freeport Indonesia is completing the first underground gyratory crusher excavation at their Deep Mill Level Zone (DMLZ) mine located in the mountains of Jayawijaya, District of West Papua, Indonesia. DMLZ is an underground block cave mine with an expected output of 80 000?t/d and a scheduled production start in 2015.In order to deliver crushed ore to the mill through the existing conveyor belt, the DMLZ block cave mine will construct two 1000?kW 1.6?×?2.3?m gyratory crushers with their own respective ore flow conveying systems underground. Each crusher is composed of top, middle, and bottom chambers with an ore bin. This system includes a series of high capacity conveyors approximately 5 km in length including transfer stations and support facilities.The development methodology required a combination of lateral development by jumbo drilling machines and vertical development by mechanised raise climbers (MRC) due to the complexity of the chamber design.This paper will discuss the project scope, design and development methodology, ground conditions, innovative survey controls, and the challenges faced due to the remote location.CITATION:Hernandez, E, Kusumohastuti, W and Agustian, I, 2014. Excavating the first underground Gyratory Crusher at the Deep Mill Level Zone mine, PT Freeport Indonesia, in Proceedings 12th AusIMM Underground Operators’ Conference 2014 , pp 43–50 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 24, 2014

Fluid inclusions and sulfur isotopic compositions were studied in a possible extension of the Toyoha polymetallic vein deposit. The objective of this work was to gain a better understanding of the ore depositional conditions, sources of ore constituents, and distribution of mineralizing fluid in the region. Fluid inclusions in sphalerite and quartz show that most homogenization temperatures range between 190¦ and 290¦C. Most salinities range from 0.0 to 3.4 wt per cent NaCl equiv. Sulfur isotopic compositions of ore minerals (pyrite, sphalerite and galena), determined by a conventional technique, range between 1.3 and 7.7 per mil. The mineralizing fluids were characterized by relatively low and various temperatures and low to moderate salinities compared to those at the southeast region of the main ore bodies (Izumo and Shinano veins) where rare elements such as tin, tungsten and indium occurred. Obtained temperatures and salinities were attributed to the mixing of hydrothermal fluids with groundwater. Sulfur isotopic data suggest sulfide sulfur was of magmatic origin. Isotopic temperatures, estimated from the isotopic fractionation factor between sphalerite and coexisting galena, are between 195¦ and 322¦C. The temperatures are only consistent with fluid inclusion homogenization temperatures in sphalerite or coexisting quartz when sphalerite was a honey-yellow coarse crystal lacking conspicuous colored growth bands. This suggests the detailed classification of mineral pairs growth textures will be necessary for precise in situ measurements to obtain reasonable eothermometric results.

Jan 1, 2002

By F C. D Michelin

As mines get deeper, the critical underground temperature limits will be exceeded, and an increasing number of mines will need to implement, expand or modify cooling systems. Surface cooling plants have many advantages over underground cooling such as efficient heat rejection, and lower relative capital cost; however the delivery of cooling through long underground distances can result in lost refrigeration capacity before the chilled air reaches the areas it is needed most. Refrigeration plants are therefore often overdesigned in size and capacity to compensate for underground losses.More mines are now utilising real-time monitoring and automated control of ventilation airflow and fan systems to ensure the conditions underground are safe and productive, and power consumption is efficiently managed. There may be significant opportunities to extend ventilation monitoring and control into the refrigeration delivery and control system.Energy reduction is an effective way to reduce costs and CO2 emissions, which is an increasingly important part of corporate governance. More efficient refrigeration control is a further step toward reducing energy consumption. This paper looks at an added step in how real-time monitoring can assist in controlling the output and chilled air delivery of a cooling plant. The requirements, implementation, benefits and challenges will be discussed.

Oct 12, 2022

By C Li, S Wang, L Qiao

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

Jan 1, 2000

Iron and steelmaking slags have been utilised for a century. All dumps are now exhausted. Because of constraints in establishing new stock yards, all slags have to be utilised immediately. At present, this is being achieved. Only in a situation where there is an increase in pig iron and crude steel production, together with the impact of new residual materials competing from other industries can marketing problems be anticipated.

Jan 1, 1979