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By A Bennett, A Peck

BHP has recently constructed a Hot Briquetted Iron Plant at Port Hedland in the Pilbara region of Western Australia. Supply of iron ore fines to the plant is by conveyor from the companyÆs existing Nelson Point stockyards. The conveyor passes under Port Hedland harbour in a concrete segmentally lined tunnel, approximately 1030 m long and with a 5.1 m external diameter. The tunnel was constructed by a Tunnel Boring Machine (TBM) which both excavated the ground and erected the tunnel lining. The tunnel was bored between cut and cover in situ concrete portal structures, the TBM being launched from the Finucane Island side towards Port Hedland town. The alignment required lengthy gradients of 1:6 on either side of the harbourÆs dredged channel, under which the tunnel is bored with a minimum clearance of 8 m.The tunnel is fitted-out with:1800 mm belt conveyor capable of 10 000 tph;walkway along which a specially designed inspection/ maintenance vehicle can run; andtunnel services including power, light, fire detection and suppression communications, water mains for wash down and sumps and pumps for drainage.This paper gives a general overview of the design and construct contract, important aspects of the design and the construction process itself.

Jan 1, 1999

The narrow quartz vein deposits at Konongo and Ghana Main Reef gold mines in Ghana were emplaced during the plastic flow cross folding of pre-existing sub-isoclinally folded volcanic and perivolcanic deposits of Proterozoic age. The older fold structures tightened differentially according to their position in relation to the axes of the cross fold pattern giving complex outlines to the reefs in both plan and cross section.Some 4500 measurements of bedding plane linears were used in the resolution of the Boabedroo footwall structure at Konongo. The methodology developed at the Boabedroo mine was then successfully applied to other complex bodies at the Konongo and Ghana Main Reef mines.All mine development, especially stope preparation, of the folded quartz reefs at Konongo and Ghana Main Reef was controlled by the geologist to ensure that the veins were removed with as few geologically enduced hiccoughs as possible.

Jan 1, 1993

By J Hadjigeorgiou, T R. Stacey

A ground support system is a combination of individual reinforcement and surface support elements that work together to retain and contain the rock mass. The various elements are subjected to external loads and to interactive loading between individual ground support system components. This paper focuses on the challenges in determining the capacity and behaviour of mesh, recognizing that installed mesh can be subjected to several loading mechanisms. Field observations from underground hard rock mines demonstrate that there are multiple types of damage and modes of failure of mesh. However, these are difficult to reproduce in a laboratory environment. A critical review has shown that existing mesh laboratory testing rigs reproduce very limited loading conditions that may not be representative of underground conditions. This has significant implications in quantifying and extrapolating the performance of mesh to ground conditions. CITATION:Hadjigeorgiou, J and Stacey, T R, 2018. Challenges in determining the capacity of mesh, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 280–290 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

After the last world war, management tended to change from an acquired skill more associated with experience than formal training, to a specific widely-recognised specialism requiring an involved formal education process.That process, of necessity, required the development of business schools, M.B.A. courses -indeed the setting up of professional chairs to deal with the intricacy of general management development.Management research burst forth bringing forward new and exciting theories which developed new techniques, tools and terms.

Jan 1, 1985

By Burton E, Eaton R

The incentive to improve wear resistant materials performance is examined with respect to plant availability and recent trends in the labour force. Standard practice at Isa Mine Concentrat- ors in countering the effects of abrasive and corrosive wear is discussed with emphasis on results with more exotic materials such as ceramics and the Cr-Ni-Mo white irons. The paper updates work on rod and ball mill Linings.

Jan 1, 1978

With the introduction of the Health and Safety in Employment (HSE) Act 1992 and the subsequent repeal of regulations pertaining to mining, there has been an upheaval of the management of health and safety in mines.  More than ever, employers know that they must ensure that their workers are competent to carry out their assigned tasks.

Jan 1, 1997

Interrelated data for five fundamental features of production processes would help promote the- development of the discipline and profession of extractive metallurgy. The features are the input materials, the products, equilibria, kinetics" and movement of materials within the reactor. Aspects of overall process performance that could be developed in these terms include quantitative comparison of reactor engineering options, process dynamics, interruptions to operations, and recycling. The ability to be able to forecast these and other aspects of process performance would be valued by most metallurgists. Although data have been reported for each of these aspects they have been more relevant to process economics than process fundamentals. The data have not often been interrelated via the fundamental features for a particular raw material-process system; nor have ~ similar data been related for different systems.

Jan 1, 1986

The continuously growing coal mining industry of India presently includes shovel dumper combinations in open cast mines, sometimes with dragline mining of overburden, together with the whole range of longwall and bord and pillar underground mining, continuously undergoing fuller mechanisation. This transition from "low tech" to "high tech" systems is now monitored for reliability and provides bases for comparisons of downtime relative to age and make of equipment, whether imported or indigenous, including spare parts, as well as frequencies of particular failures to allow analysis and progressive improvement. Varying geologies complicate technology and equipment requirements, especially in underground mine,s with minimal technological standardisation, but now, reliability in South Eastern Coalfields Limited has been given more importance and superior technological back-up is being developed.

Jan 1, 1991

By Quast K. B, Newell R, Caterford J. H

The most common reason for gold-bearing deposits being refractory is the presence of sulphides; in many cases these interfering minerals contain arsenic, antimony, or other environmentally-sensitive elements. A number of processes have been proposed or developed for pre-oxidation of interfering minerals. In most cases developers have focussed on gold recovery and capital costs, with relatively little data on the deportment or form of these potentially harmful elements. This paper surveys recent work connected with pressure pre-oxidation processes. Data from pilot plant treatment of refractory gold materials, using the nitric acid Redox process, is discussed along with the attendant flowsheet and engineering implications. Four refractory gold-bearing materials have also been tested at the University of South Australia for arsenic and antimony deportments.

Jan 1, 1991

The process of establishing the design criteria is the key step in commencing a new project.. The method for establishing design criteria and translating them to a workable plant design is described. INTRODUCTION The use of activated charcoal to recover gold from alkaline cyanide leach liquors is the most rapidly expanding technology in hydrometallurgy today. The process, known as carbon-in-pulp (CIP), has replaced countercurrent decantation as the method for recovering gold by cyanidation. Carbon-in-pulp entails mixing activated charcoal with a ground ore-water slurry containing gold cyanide, allowing the charcoal to adsorb the gold, and then mechanically removing the gold loaded charcoal from the pulp. The pulp is sent to tailing disposal and the loaded charcoal is sent for gold bullion production. Activated charcoal's affinity for gold has been docu- mented for over one hundred years. In the first cyanide plants, one of the preferred methods of stealing gold was to place a piece

Jan 1, 1982

By Butcher NM, Walker GS

Argyle Diamond Mines Pty. Limited (ADM), manager and operator of the Argyle Diamond Mines Joint Venture (ADMJV) will recruit approximately 400 employees during 1985 to operate the new large-scale, open-cut diamond mine and treatment plant being developed at Argyle, in the East Kimberley Region of Western Australia. These employees will live in Perth or environs and will commute to work at Argyle via chartered jet aircraft. On site, they will be accommodated in self-contained single person's quarters, with central messing and recreational facilities. Rostering systems have not been finalised, but it is likely employees will rotate through a cycle of 14 days at site and seven-days on leave in Perth. ADM spent three years evaluating residen- tial options before deciding to commute its workforce from Perth. Another 70 senior staff will reside in Kununurra (the nearest established town, 250 km from Argyle) and commute to the mine daily by air.

Jan 1, 1984

The Mining Act (1992) and the Petroleum Act (1980) provide for the Government of Papua New Guinea (PNG) to take up equity holdings in mining and petroleum projects. The price the Government pays for its share is based on the historical cost of exploration and development on the project to the date of government equity acquisition. The equity level to be acquired is not fixed and ranges up to 30o for mining and up to 22.5s for petroleum at the discretion of the Government of the time.The objective of this paper is to examine the pros and cons of State equity holdings in PNG from the point of view of both the State and the developer. Using an economic model of the PNG mining taxation system an assessment is made of the effective return on investment received by the State from such equity holdings. The results are compared with government revenues from other taxation measures.

Jan 1, 1994

By Geoff Baldwin

The use of monitors to assess equipment performance is carried out on a routine basis in many industries. The benefits gained through process control in knowing exactly how the equipment is working far outweigh the initial capital costs of the monitor. In the mining industry several dragline monitors have been developed and installed on equipment through out the world, but to date none has been fully accepted by the industry. This paper describes the use of a sophisticated monitoring system which incorporates an onboard processor to assess both dragline and blast performance. The results of a case study are presented and an indication of the potential of the monitoring system to optimise mine production is given.

Jan 1, 1990

Silver and gold bearing ore from the Palmarejo mine, located within the Mexican state of Chihuahua, contains a complex mix of electrum, native silver, silver sulfides and silver chlorides. This paper presents a case study that describes the selection, development and engineering of a tailored process plant for the recovery of silver and gold from this ore. Process circuit feasibility study modelling, metallurgical test work and engineering studies are outlined. Options considered to optimise the recovery of the contained silver and gold are compared, based upon cost, operability, recovery and engineering aspects. Concentration by flotation was found to be the preferred primary recovery route. Intensive leaching of the flotation concentrate resulted in solution grades sufficient to allow direct electrowinning to be evaluated against the more traditional Merrill Crowe process. The flotation tailings stream is processed through a separate leaching stage as there is sufficient economic metal extractable from this stream. The processing flow sheet, which is designed to maximise the recovery from both the flotation concentrate and tailings, and to utilise a common metal production facility, is presented.

Jan 1, 2009

Drill and blast operations account for 12 - 15 per cent of total mining costs. This paper looks at a comparison between electronic detonators and non-electric detonators, focusing on the cost benefits associated with the high precision of the timing sequences of electronic detonators. An analysis of the total mining costs was made on two main case studies; one on a quarry in South Australia (Martin, 2007) and the other on a project undertaken at Sunrise Dam (Vaughan et al, 2007). The criteria used in the analysis included; the resulting fragmentation, a vibration analysis, crusher throughput and productivity analysis such as excavator cycle times, dig rates of the excavator and bucket fill factor. The results indicate that there were consistent production improvements and hence reductions in total mining costs attributed to the use of electric detonators. An increase in the degree of fragmentation gives lower crushing costs as more material passes through as undersize. This reduces truck delay time at the crusher, which in turn gives higher truck and shovels productivity as well as higher dig rates for the excavators.

Jan 1, 2008

Timestudy analysis of mining operations at North Broken Hill Limited has been carried out by dissecting operations into small elemental components, and accurately timing these elements. Over a wide range of observations, this has enabled standard time values to be calculated for all underground work.The application of the standard values is in calculating performances as a measure of work output and Performance Controls are kept on approximately two-thirds of underground employees. Through the Controls it has been possible to stimulate supervisory action to improve low performance, and to reduce delays and lost time.The values are used to calculate contract" prices, and anomalies in previous prices have been adjusted on work values and not on arbitrary standards. In out-of-the-ordinary circumstances, the request for a timestudy investigation has been made by both operatives and foremen, and the contract set following the timestudy analysis has been to the satisfaction of both parties.The range of values enables contracts to be applied to work which was previously performed on a day basis, resulting in improved performance.A natural corollary of timestudy is the analysis of methods, and in some cases method improvements have been introduced.It is anticipated that further investigations will be made on methods.INTRODUCTIONIn 1953, a Timestudy analysis of mining operations at North Broken Hill Limited was commenced under the guidance of management consultants. Its aim was, to determine standard time values for specific operations, which would provide management with a measure of productivity beyond the existing measures of tons or feet of advance, and also to determine whether increased output was available under existing operating conditions.

Jan 1, 1956

By C M. Hill

This paper aims to provide a brief overview of the Australian Coal Bed Methane (CBM) industry and more importantly the challenges to sustainable management of the industryÆs by-product, groundwater. In a country where water is scarce and having gone through one of the worst recorded droughts it is vital that this important industry be seen to be managing water in a responsible manner with the greatest environmental and social benefit. Benefits of the water from CBM wells can be enhanced through treatment to produce potable water for domestic or stock purposes, water for irrigation or aquaculture or lower quality or untreated water for industrial or mining purposes. Other options are re-injection of raw water or waste from the treatment processes or discharge to surface waterways. The critical change and difference between CBM projects and traditional oil and gas operations should be that where possible water is no longer disposed of via evaporation ponds with the dual legacy of waste of the water resource and an environmental contamination problem with the remaining salt and brine product.

Jan 1, 2003

By Menne DM

The carbon-in-pulp (CIp)process has become well accepted and firmly established in the gold industry of South Africa and, at this stage, six large CIP plants are treating close to I million metric tons of material per month. Many small operators are also using CIP and additional large plants are either nearing completion, are on the drawing boards,. or are being considered. The programme of testwork that preceded the acceptance of the CIP process in South Africa was conducted over some eight years and has been previously described'-7. With the start-up of the President Brand CIP plant on 'calcine' in July 1980 and that of the Western Areas CIP plant on repulped filter residues in September 1980, the emphasis on the CIP process switched from pilot plants to these large plants - and has largely remained there. As it has started up, each new CIP plant benefited from the experience gained and the developments made, on earlier plants but, since so few plants have so far been established in South Africa, each new plant and each new design has revealed a further set of conditions to be met and problems to be overcome. However, in the highly collaborative atmosphere of the South African gold-mining industry, the results and observations from the operation of these first plants were shared by all mining groups. This paper will attempt to describe typical developments on, and results obtained from, these new large plants, and will incorporate significant results from the earlier laboratory and pilot-plant investigations.,

Jan 1, 1982

Mine planning is difficult. Even for small operations, it involves reasoning with complex variables and the practical difficulties of mining. It is also about predicting and planning the future in an unpredictable physical and economic environment. Yet we rely on a handful of individuals and their spreadsheets to tell us how to do it û planning the business and activities of mining to hopefully produce results that will please stakeholders. Does it work? Not as well as it could. Planning affects everyone in the organisation. Company executives are demanding more reliability and stability in cost and revenue forecasts from their operations. Management want to explore ways of being more cost effective. Miners and contractors want more useful plans and realistic targets. And the planners have to describe the method that will translate business objectives into implementable plans. Even with the use of computer technology a lot of effort is expended to produce plans that are largely qualified by the level of knowledge and experience of individuals. Better use of information and the application of Intelligent Technologies can improve the quality and reliability of mine plans and schedules. By capturing the knowledge within the organisation and speeding up the planning process, Intelligent Technologies allow more options to be considered more rigorously. But it is not just about technology. It is about how technology is implemented and embodied in the way the business is managed for performance. When this happens, the real benefits of better planning start to flow.

Jan 1, 2003

By N Udugampola, d A. Seneviratne, X Ai, B Li

With the evolution of mining technology, wireless mesh networks using low-power, long-range technologies such as LoRa are increasingly utilised in underground mining operations. Efficient deployment of wireless nodes in such mesh networks necessitates understanding radio wave propagation behaviour in underground mines. While existing propagation models either remain theoretical or apply only to basic geometric shapes, we propose a practical approach to analyse radio wave propagation behaviour in underground mines using ray tracing simulations with reconstructed 3D models of targeted environments. Our method validated using a set of corridors as a substitute for underground mine environments, involves constructing a 3D model using SolidWorks from LiDAR scans of the environment and performing wireless transmission simulations using the MATLAB ray tracing toolkit. Our simulation model is also fine-tuned by calibrating the raytracing parameters based on real-world LoRa transmission experiments in the actual environment corresponding to the 3D model. This method offers a practical solution for optimising wireless node placement in underground mines, facilitating efficient network deployment while reducing the need for extensive physical testing of radio wave transmissions.

Sep 1, 2024