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Sampling errors result from heterogeneities within the lot under study. Within a rock mass in situ heterogeneity results in the geological nugget effect, which accounts for most of the natural variability. In broken rock, constitution and distribution heterogeneities are important. A major result of the constitution heterogeneity is the Fundamental Sampling Error (FSE) which is the smallest residual error that can be achieved. It cannot be eliminated, but can be minimised and refl ects the fact that the broken rock sampling process is never completely free of error. Together with other sampling errors, FSE contributes to the total nugget effect. The FSE for a sampling protocol can be evaluated using the so-called Gy equation. Its practical applications to low-grade gold ores have often been unsuccessful due to problems linking the FSE and minimum sampling mass and the defi nition of key parameters such as the liberation diameter. Well-designed sample protocols minimise the total sampling error and hence the nugget effect. Reduction of the nugget effect is a key requirement for all sampling programs whether related to exploration and resource evaluation, metallurgical test sampling, grade control or metallurgical plant sampling. This contribution reviews the relationship between heterogeneity, FSE and nugget effect in gold deposits; and emphasises the need for FSE management throughout the mine value chain.

Aug 1, 2010

By T Trott, G Lumley

"The mining industry suffers from a shortage of professional and other workers. Research and analysis has demonstrated a close correlation between high performance in productivity, maintenance and safety. There is also a significant correlation between engagement and performance. It is the hypothesis of the authors that mines can use a strategy of establishing themselves as a high-performance mine to attract and retain high caliber professional people: step 1 is to become best practice in equipment performance (productivity, maintenance and safety) step 2 is to brand the mine as æbest practiceÆ by sharing what has been confidential performance and outcome information with the general industry.Previous research has shown that many professional people are attracted by the prospect of a high achieving site because of the learnings and the support for continually doing better. In addition, a link has been established in previous research between productivity and safety. Operators and drivers are attracted to sites which have fewer dangerous people operating or driving. Good management delivers exceptional performance and a work site which high caliber managers and operational personnel people want to work at. The strategy requires commitment and proper execution but it can work. The strategy needs a specific approach and this paper will discuss this. A case study is provided from a mine which over a nine month period increased dragline performance by 15 per cent and reduced stress on the boom by 30 per cent. This mine paid the employees (professional and operational) $25 000/a less than the major mines but the operators and professional people would not leave; in fact, people were happy to be paid less to work there.CITATION:Lumley, G and Trott, T, 2012. Using best practice operations as a strategy for attracting and retaining professional people, in Proceedings International Mine Management 2012, pp 35-52 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 20, 2012

By D J. Williams, C Zhang, F E. Herrera Cabrera

Farming on bauxite residue using screw propelled equipment (SPE) has been commonly practised to accelerate dewatering and as it promotes consolidation and enhances storage capacity. However, it is unclear when and how often farming should be conducted during the transition of bauxite residue from slurry to dry solids and how deep each slurry deposition should be. To address this issue, three desiccation tanks were established in the laboratory to investigate how much farming could enhance the desiccation and consolidation of tailings. The cuboid tanks, of 350 mm in height and 300 mm in width and length and with an opening on the top, were placed on load cells to monitor the water loss during desiccation and were instrumented with moisture and suction sensors designed and developed at the University of Queensland to measure the water content profile of the residue. The bauxite residue, composed of silt-size particles with low plasticity, was hydraulically deposited in the tanks as a slurry at 27% solid content, resulting in 100 mm depth of solid material settling. Evaporation was enhanced by placing two identical electrical fans above the tanks. Two phases were conducted. In the first phase, the two tanks were left untouched for evaluating non farmed conditions and for calibrating sensors, while in the second phase, three tanks were subjected to atemporal farming using purpose-built screw propelled equipment. The experiment was terminated when the residue was completely desiccated. This paper reports on the instrumented tank set-up and the results obtained to date.

Jul 1, 2021

By B Smith, R Gelson

Springvale Colliery is an underground longwall mine situated approximately 10 km north-west of Lithgow in the western coalfields of New South Wales. Following a full-scale review of the mineÆs ventilation system in mid-2010, it was clear that the mine by early 2013 would become ventilation constrained as a result of the increasing size of the mine workings, the predicted worsening tailgate conditions and plans to introduce a fourth continuous miner unit. This realisation led Springvale to embark on a major upgrade of the mine ventilation system that would meet short-term and life-of-mine (LOM) requirements.Included in the upgrade project was the installation of a new high pressure centrifugal main exhaust fan that is capable of overcoming the high resistances imposed frequently on the circuit by restrictions in the tailgate airway. The new fan featuring a 2.5 MW motor is designed to be capable of operating at a quantity of 250 m3/s at a pressure of 7.9 kPa, a substantial improvement over the previous system, which had an operating duty of approximately 145 m3/s at 1.9 kPa. The new fan is of a centre hung design and features a backup diesel motor to maintain ventilation in the event of a power outage.Structural engineering analysis determined that under the operation of the new main fan the existing standard of ventilation control devices (VCDs) at Springvale would not be adequate to withstand the increase in differential pressures. As such, an upgrade of critical VCDs was undertaken utilising a novel high flexural strength (9 MPa) shotcrete and thin spray-on liner, which help serve to safeguard the structural integrity of the appliances and prevent increased leakage as roadway conditions at VCD sites deteriorate over time (a serious problem in many areas of the workings at Springvale).In addition to the main ventilation system upgrade, a separate upgrade focusing on improving development face ventilation was also undertaken. This upgrade included the purchase of two high capacity (22 m3/s) variable inlet vane (VIV) auxiliary fans to facilitate comfortable development face ventilation.The upgrade of the mine ventilation system at Springvale has been three years in the making, but has removed a major business risk in that it has afforded mine planning and operational flexibility (a fourth unit can now be introduced) for the LOM, and importantly provided unprecedented levels of comfort to operators at the working faces where previously ventilation and heat issues were frequently reported. The impact of this on the morale of the workforce, and hence their output, should not be underestimated.CITATION:Gelson, R and Smith, B, 2013. Life-of-mine ventilation system upgrade at Springvale Colliery - A case study, in Proceedings The Australian Mine Ventilation Conference , pp 79-86 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 1, 2013

By G Dunstan

The Ridgeway gold mine has been an enigma of the international underground hard rock community for nearly 20 years. It nearly didn’t eventuate as it was more than 500 m below a farmer’s paddock in Central New South Wales when the exploration team, looking for open pit deposits, got a sniff on its last attempt and then drilled the high-grade discovery hole. It took separate studies to find an economic mining approach. Newcrest, then a mid-tier mining company, took the venture that set it on a path of growth and built what was to become the backbone of the company for the next 15 years.The initial mining method was sublevel caving (SLC) for the upper 300 m of the orebody. The nameplate production rate for the SLC was 4 Mt/a, which was reached in June 2002 shortly after the commissioning of the materials handling system. The ultimate production rate was subsequently lifted to around 6 Mt/a through a series of innovative and efficiency initiatives. In June 2007, approval was granted for the development of a block cave (BC) operation to extract the ore reserve situated immediately below the existing SLC operations, Ridgeway Deeps. The BC was designed at approximately 6 Mt/a to match the concentrator and a systematic improvement process through the entire underground system again saw delivery rates consistently around 10 Mt/a.In line with the production rate increases, Newcrest was also committed to advancing caving knowledge through a number of targeted research and development experiments and new processes. These were primarily related to improving cave ore recovery through systematic draw marker trials, cave propagation through preconditioning techniques with associated monitoring systems. New technologies were also developed to improve the safety and efficiency of the mine through data collection, cave establishment techniques, production dispatching and autonomous loading.CITATION:Dunstan, G, 2016. The truth is stranger than fiction – the story of Ridgeway gold mine, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 19–30 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By N Burgio

Block cave mines are often thought of as rock factories where high volumes of production are mined from a fixed area suggesting little requirement for geological input and control. Yet caving operations have peculiar and specific technical requirements from prefeasibility through to post-mining reconciliation. Whilst essential elements such as resource definition, geological interpretation and sampling strategies are common to all mining methods, planning for a block cave requires a different emphasis and philosophical approach in how we deal with these issues. We will examine why a geoscientist’s input is critical towards the successful planning, design and monitoring of a caving operation.

Aug 22, 2011

By B P. Micke

Central Norseman Gold Corporation was established in 1935 and has been mining on the Norseman field in Western Australia since then. It is Australia’s longest continuously operating gold mining operation at nearly 80 years, although it has had its periodic challenges in the intervening years.Over the last 40 years, a series of open pit mines around the Dundas Goldfield have supplied lower cost mill feed to the Phoenix Mill at Norseman from time to time but this has largely come to an end for the foreseeable future. Now that underground ore sources are once again the principal mill feed, there are several challenges to be met for an ongoing profitable operation.During the last 20 years, there have been three different owners and this has affected the manner in which the operations were managed quite significantly. These differing approaches are contrasted and examined in some detail from both the operational and financial aspects.Planning of a downsized operation to ensure sustainable profitability in the future in a mining environment where there has rarely been more than two to four years of reserves ahead of the mill for planning purposes has been a significant challenge. Several of the options examined are described, including alternatives for future mine development.CITATION:Micke, B P, 2014. Managing the margin at Norseman, Western Australia – a case study, in Proceedings 12th AusIMM Underground Operators’ Conference 2014 , pp 119–128 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 24, 2014

By Wetzeil N

High ambient temperatures combined with high surface humidity in the north of Australia and, in particular, the northern areas of the Northern Territory can make underground workplaces relatively inhospitable at certain times of the year. . Woodcutters' silver/lead/zinc mine, situated some 80 km south of Darwin, would be the most northerly underground operation of any significance in Australia. As such, during the build up to the wet season, it has a particular problem of ventilating a deep underground mine with already high dry and wet bulb temperatures at the surface. The Mine Management Act and Regulations mention only that workplaces shall be 'in a fit state for a person to work in or occupy'. Woodcutters therefore set in progress a Heat Stress Program to endeavour to set standards which would be more measurable and justifiable. The aim of the program was to compile a record of ambient atmospheric conditions in the working areas such that areas and/or work activities generating high ambient temperatures and humidities could be identified, quantified and qualified. Once the analysis stage of this program was completed, Woodcutters compiled a set of recommendations for the continued monitoring for, and control of, heat stress conditions to ensure that no underground employee was placed at risk from 'heat stress'. These recommendations are discussed in this paper.

Jan 1, 1994

As the surrounding environment continues to change and evolve, mine managers face a changing climate of expectations. TodayÆs mine managers must juggle competing pressures to deliver sound social, environmental and economic results. Leadership is a fundamental tool for the effective mine manager. Whilst mine managers require solid technical and operational skills, importantly the manager must be able to engage a workforce, build and retain employees and seize opportunity for growth and development when presented. An important tool for engaging employees in the business at Rio Tinto Aluminium is the business improvement programme. At Rio Tinto AluminiumÆs Weipa mine, the business improvement methodology Six Sigma is used to deliver measurable, sustainable outcomes for the business. The next step in Rio Tinto AluminiumÆs improvement journey is to implement Lean Manufacturing at all managed operations. The operating environment for mine managers continuously evolves and effective mine managers must be flexible and adaptive to meet challenges. Governance and regulation constantly change in an environment of commodity cycles and finite resources. This increases pressure on the economic return achieved by the operation. As such, effective mine managers must be aware of and manage the operating environment û the broader, issues-based environment not just the immediate day-to-day responsibility of mine managing. This includes delivering on safety, community and environmental priorities. At Rio Tinto Aluminium, part of managing the business is via investment in the area of social partnerships to engage employees and the broader community in Rio Tinto AluminiumÆs commitment to sustainability. The Future Reef partnership entered with the Great Barrier Reef Research Foundation in 2005 forms an important part of Rio Tinto AluminiumÆs climate change strategy. This four-year, A$1 million investment funds programmes looking at the effect of ocean acidification on the Great Barrier Reef. The partnership is a unique example of industry and science working together on an area of mutual and national concern. Modern mine managers require a broad set of skills to effectively deliver outcomes. TodayÆs mine managers must make innovative and courageous responses to determine todayÆs strategy for tomorrowÆs future.

Jan 1, 2006

By C R. Fountain, W R. Cannings

The zinc-lead-silver mineral resource at Lady Loretta ranks amongst the worldÆs richest when measured in terms of in situ metal grades. However, the project remains undeveloped 28 years after its discovery in 1969. The primary obstacle to development has been the fine and complex grain structure of its ores, which make flotation concentration inefficient even with fine grinding. The size and remote location of the deposit have also hindered exploitation. BUKA planned to directly fume the volatile target metals from the ore when it acquired the project. Intensive, post-acquisition modeling showed the innovative processing route to be uneconomic, notwithstanding high metals recovery and low waste content in fume product. Progressive modifications and supplements to the underlying fuming process enhanced economics and resulted in a new mine-to-metal processing route for zinc-lead-silver ores. The proprietary, three-stage BUKA Zinc Process offers technical, economic and environmental advantages. It is expected to find widespread application in the treatment of ores and residues. However, neither continued R&D nor application to Lady LorettaÆs currently delineated resource can be justified under prevailing market conditions. The objectives and results of each step in the process development sequence are outlined with reference to their impact on the commercial viability of the Lady Loretta project.

Jan 1, 1998

By L Lachance, F Flament, D Leroux, S Gariépy

The pervasiveness of poor sampling practices in and around mineral processing plants could seem intriguing in view of the various documented evidences both for causes and consequences. To this extent, this paper revisits the well-documented but lesser-known fact that failure to care sufficiently about how samples are selected and managed is the mother source of almost all sampling biases. The authors believe that the potentially huge leverage between causes and consequences as well as the diversity of people involved in sampling call for a globally integrated solution rather than for a point solution. Such a globally integrated solution has already been put forward by the AMIRA P754 Metal accounting – code of practice and guidelines (AMIRA, 2007) that inherently requires accuracy to be targeted, measured, reported and managed. Furthermore, always in order to avoid a point solution, several layers of protection against biases must be put in place with each one involving a different ownership whenever possible. This is exactly the role intended by the supervisory bias detection method described in this publication. It is based on the continuous monitoring of the expected value of reduced residuals obtained from statistical data reconciliation conducted in a metal accounting context. This supervisory bias detection method is developed in full details after which Monte Carlo simulations are done on a mineral processing plant example for showing how it can be successfully applied for detecting hidden biases.CITATION:Lachance, L, Leroux, D, Gariépy, S and Flament, F, 2014. Detecting sampling biases in metal accounting, in Proceedings Sampling 2014 , pp 109–120 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 29, 2014

By L Galisson, E Audigé, D Sowers

Establishing a robust geotechnical instrumentation and construction monitoring plan is one of the keys to the successful delivery of the world’s largest soft-ground bored tunnel in Seattle, Washington. The paper describes and provides a return of experience on current and best practice for monitoring tunnelling projects in urban areas. The owner’s contractual approach is discussed to highlight the flexibility of the design-built contract in achieving equal or better solutions by allowing for the use of innovative technics. Special attention is given to the management and involvement of third parties (building owners, utility owners), including the public, to overcome all challenges faced during the installation of the monitoring system in downtown Seattle for over 1000 instruments. Finally, the authors present the strategies implemented for managing the monitoring data and communicating with the owner, contractor and stakeholders.CITATION:Sowers, D, Galisson, L and Audigé, E, 2014. Current and best practice for monitoring tunnelling projects in urban areas – Alaskan Way bored tunnel, Seattle, Washington, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 441–450 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By R Moreby

This paper is a demonstration of the techniques developed during an Australian Coal Association Research Program (ACARP) funded research project aimed to develop aids, principally computer based, to assist mine personnel to more efficiently manage significant incidents in coal mines. These aids include software to aid in the location of the incident, electronic information storage and retrieval, online site emergency response manuals and software to aid in decision-making.

Jan 1, 2005

By B Dodd

This paper details how the Australian Securities and Investments Commission (ASIC), as a disclosure and conduct regulator, approaches regulation of continuous disclosure, capital raising and control transactions in the mining and resources sector, and the reasons for the approach. In examining this topic the paper considers the Joint Ore Reserves Committee (JORC) Code (JORC, 2004), the VALMIN Code (VALMIN Committee, 2005), the relevant ASX Listing Rules and the relevant provisions of the Corporations Act 2001 (Corporations Act). This paper discusses ASICÆs approach to expert reports and disclosure with reference to Regulatory Guides 111 Content of expert reports and 170 Prospective financial information.CITATION:Dodd, B, 2012. Issues in capital raisings and disclosure, in Proceedings International Mine Management 2012, pp 3-14 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

By D J. Gray

The 4 km long Huguenot Toll Tunnel in the Western Cape region of South Africa celebrated its tenth anniversary on 18 March 1998. At present a single (South) bore with bi-directional traffic flow is operational. The North bore was originally excavated but not lined and equipped.The tunnel is fitted with a semi-transverse ventilation system comprising 45/350 kW two speed fresh-air and 1 MW exhaust air fans at each of the portals. These provide ventilation through fresh and exhaust air ducts above the ceiling separated by movable partition doors. Secondary air ducts deliver air at low level. The fan control depends on the levels of CO pollution or visibility measured at six positions along the tunnel.The system performed well during initial tests and under conditions of low traffic volumes. As traffic volumes increased, and user complaints of bad air in the tunnel were received on several occasions, we realised that we had a problem. Tests confirmed that natural airflow within the tunnel induced by prevailing meteorological conditions outside the portals affected the performance of the ventilation system causing a plug of bad air to be trapped at varying positions along the operating tunnel.The control systems in the tunnel are presently being upgraded as described by Gray, Rieckert and Bullock (1998). As part of the retrofit we are implementing a new control strategy for the ventilation system which takes into account the external weather conditions. This paper discusses the 24 month long meteorological data gathering exercise, which is on-going, and explores the philosophies planned for controlling the ventilation system. The correlation between winds external to the tunnel and induced airflow inside the tunnel are examined. The effects of the weather induced airflow on the existing ventilation system are considered and proposals given for taking these effects into account in the new control strategy. These include the implementation of an expert system to predict ambient airflow from prevailing weather conditions, and the use of airflow measurements taken in the uncompleted North bore as a cross-check.The paper highlights the need to take cognisance of external weather conditions when designing tunnel ventilation systems.

Jan 1, 1999

By A Giblett, M Daniel

"The Global Mining Standards and Guidelines Group (GMSG) currently supports nine individual industry working groups focused on developing standards and guidelines for the mining industry. In 2013 the GMSG established the Industrial Comminution Efficiency (ICE) working group to develop freely available guidelines for plant operators to quantify the operating efficiency of industrial comminution circuits. This initiative has engaged a diverse group of representatives from mining companies, equipment vendors, consultants and metallurgical laboratories with vast experience and capabilities in the field of comminution. The GMSG has issued the first two guidelines from the ICE working group in 2015–2016, with the third guideline having completed the approvals process and being in the final stages of editing ahead of release later in 2016.Two of the ICE guidelines present methods to quantify comminution circuit efficiency, and a complementary guideline describes best practice methods to collect the necessary samples and data to furnish these assessments. Collectively the guidelines cover sampling, survey data collection, laboratory testing procedures and calculation processes to allow the user to generate a relative circuit efficiency factor for the comminution circuit at the time of survey. The reference energy consumption is calculated considering the measured F80, P80 and ore strength at the time of survey, using either or both of the Bond or Morrell methods presented in GMSG guidelines dedicated to each method. The guidelines consequently provide the end user with practical tools to perform circuit efficiency analysis and to readily quantify the impact of optimisation efforts.This paper presents the content of the three ICE guidelines and describes their intended application.Citation:Giblett, A and Daniel, M, 2016. Global Mining Standards and Guidelines for Determining Comminution Circuit Efficiency, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 3–8 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

By J Jardine

An improved ground support method for development intersections, wide spans and stope brows was implemented at Kanmantoo mine. The method uses a jumbo to simultaneously drill and install self-drilling anchors (SDAs) to depths from 4.5 m to 7.0 m. Resin is subsequently pumped into each SDA using a specially designed integrated tool carrier basket, with plating occurring within 10 mins due to rapid resin cure. This methodology means that SDAs can be installed rapidly due to reduced process steps and wait times with reduced hazards to personnel. Cablebolts are used extensively in underground mines to reinforce the ground in wide spans, such as at intersections and stope brows. The flexible cablebolt tendon allows for a long, continuous and high-capacity reinforcing element to be inserted into the rock. A common cablebolt installation practice at Australian underground mines that do not utilise a mechanised cable bolter, is for cablebolt holes to be drilled by a jumbo or longhole rig, hand installation and grouting by a service crew, then plate tensioning following a grout curing wait time of typically 12 to 24 hours. This process involves multiple separate labour-intensive work processes and results in reduced availability of priority headings. This paper discusses the development history of vertical SDA use in wide spans at Kanmantoo mine. The installation process is fully described, including aspects such as reliable in-hole coupling of SDAs, resin selection and pumping aspects. A cost benefit assessment, and a case for ground stability are presented to compare cablebolt use to SDAs in development intersections.

Mar 29, 2023

By C L Humphrey

Biological monitoring programs for environmental protection require techniques that will provide both early detection of possible adverse effects, and assessment of the ecological significance of these effects. Monitoring techniques must include responses sensitive to the impact, that can be subjected to rigorous statistical analysis and for which statistical power is high. Such issues in baseline research of 'what and how to measure?' and 'for how long?' have been the focus of a program being developed to monitor and assess effects of mining operations on the effectively pristine, freshwater ecosystems of the Alligator Rivers Region (ARR) in tropical northern Australia. Application of the BACIP design, utilising a form of temporal replication, to univariate data (single species) and multivariate (community) data is described. For new ventures in Australia (such as mining), monitoring programs should be designed to establish with high probability that an impact on the ecosystem no greater than a prescribed amount has gone undetected - as opposed to simply allowing development to continue as long as 'proof' of impact is not available. Such a precautionary approach represents a shifting of the 'burden of proof' and would require with the BACIP design, a minimum number of baseline years in order to achieve some desired level of statistical power in a test for impact. Power analyses conducted on two to five years (depending upon the technique) of baseline data from streams of the ARR indicate that the BACIP design would not impose developmental constraints on mining and that a policy of reversal of the burden of proof would provide the cornerstone required for managing such development in an ecologically sustainable manner.

Jan 1, 1994

Australia has a long history of underground mining. Even withadvances in open cut mining equipment, techniques andeconomics, many orebodies are still best mined by undergroundmeans. In addition, modern exploration tools are æuncoveringÆorebodies that are at increasing depths. South African mines arecurrently producing from below 3 km, and developing down to5 km depths û it is likely that Australian mines will also becomemuch deeper over the next 20 years. One of the most significanttechnical challenges in deep mines is the problem of heat.Community expectations and legislated standards continue todrive operations towards improving the working conditions inmines. The hazards and costs associated with chronic hotworking conditions (heat illness, poor safety, poor productivity,higher operating costs and poor morale) are also becomingincreasingly recognised (Brake, Donoghue and Bates, 1998). Theexposure of miners to many other occupational hazards has beenreduced over the past 50 years. However, despite air-conditionedcabins greatly reducing the heat stress on mobile plant operators,there are still many Australian mine workers subject to levels ofthermal stress that existed a century ago. There are severalreasons for this, including a frequently-poor understanding of thephysiology of working in heat by mine management, no agreedmining code of practice for working in heat, the lack of a robust,practical-sized instrument to measure heat stress, the costpressures on the industry and, to some extent, deep-seatedtraditional management and worker practices. Howeversignificant progress has been made in many of these areas (Brakeand Bates, in press), with the net result that there is likely to be a trend towards installation of refrigeration of some form in manyAustralian mines in the future. This will add directly to the costof operation, but will also have direct and indirect benefits,including cost benefits. It should also be noted that Australia isnot at the forefront of adopting practices to manage temperaturesin the workplace: South African metal mines usually haverefrigerated cooling, and Canadian mines spend large sums onheating, with heating costs (averaged over a full year) of up to$A1 per tonne mined (Bandopadhyay et al, 1997). The history of mine refrigeration dates back to 1919 when thefirst plant was installed at Morro Velho, Brazil. By 1965, the totalinstalled capacity (worldwide) reached about 100 MW(R)i. Since 1965 the growth in mine refrigeration capacity has beenexponential, with a doubling every six or seven years (Howes andNixon, 1997). South Africa is by far the largest user of minerefrigeration, with over 300 refrigeration machines installed. This paper discusses the key design issues associated with theapplication of refrigeration in underground metal or coal mines.Whilst the emphasis is on large, surface plants, small, surface orunderground refrigeration plants can also be very effective in thecorrect application and many of the principles of design andoperation are the same.

Jan 1, 2001

It is no longer adequate when starting a new mine to simply select the best equipment. Today's competitive international commodity markets demand superior efficiency which requires systematic involvement of people in continual improvement of production and commercial processes. True Total Quality of Management (True TQM) principles provide an operating philosophy for maximising productivity and minimising unit costs of output. The presentation will show the practical and successful use of these principles. This paper will introduce the case study and provide background material on True TQM.

Jan 1, 1995