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By Kurt M. Larson

Future haulage cost projections led Foster Yeoman Limited into developing a fully mobile crushing and conveying system at its Torr Works quarry in Somerset, England. The purpose-built system has an effective throughput of 2,500 tonnes/hour and features an Orenstein and Koppel (O & K) manufactured walking frame, a Fuller-Traylor type 54 X 74 TC gyratory crusher, and unique mobile conveyor modules designed and manufactured by Foster Yeoman. Used in a single-bench operation in this 6 million-tonne per annum limestone aggregate quarry, the system is fed at the production face by 2 Caterpillar 992C loading shovels. The entire system is moved on a daily basis following production face locations.

Jan 1, 1986

By Gerald Stolarczyk

The Radio Imaging Method (RIM) is based upon electromagnetic (EM) wave propagation in the coal seam waveguide. The radio geophysics theory underlying RIM was developed by Hill of the national Institute for Science and Technology (Hill, 1984). Recent advances in radio geophysics instrumentation have increased operating range in the coal seam waveguide to almost 3,000 feet. This paper describes RIM longwall panel reconnaissance scans and tomography results.

Jan 1, 2006

By L. Lehasa

The purpose of the project was to investigate the challenges faced by Khutala Colliery pertaining to underground road construction and maintenance. Furthermore the influence of these challenges on productivity and safety requirements were taken into consideration. The operating standards required for the construction and maintenance of the 2 seam road transport infrastructure was investigated, together with reasons why the standards of operating procedure are not met. The Code of Practice put in place by Khutala Colliery was used to view the standard operating procedures. Leading practices on underground road construction were researched. The project aims to discover the gaps that Khutala Colliery must bridge to implement enhanced practices with regards to underground road construction. During the period of study, observations were carried out to determine whether the road construction standards of operating procedure were being adhered to at all times for both road construction and road maintenance. Khutala Colliery has put in place a traffic management plan, which includes safety practices and work policies that must be adhered to while travelling on underground transport roads.

Jan 1, 2012

By Wayne Phillips, Anatalia Silva, Robert Henderson, Tondo. Luis

"Kinross’ Paracatu Mine has 20 years of operational success as one of the lowest grade milloperated gold mines in the world. At year end 2005, Paracatu’s Proven and Probable Reserves were 1.18 billion tonnes at a grade of 0.40 g/t Au, containing a total of 15.2 million ounces of gold.In 2005, the plant processed 17 Mt of ore and produced 180,519 ounces of gold at a cash cost of US$274/oz. An investment of US$470 million has been approved to expand production to 61 Mtpa in 2009 which will extend mine life to 2036. During the period from 2009 to 2013 the project is expected to produce an average annual output of approximately 557,000 ounces of gold at an average cost of sales of approximately $230 per ounce.The soft, friable ore containing readily leachable gold associated with sulphides lends itself to simple processing. The process flowsheet consists of crushing, grinding, gravity recovery, flotation, concentrate leach and carbon adsorption to produce bullion bars. This paper describes the current operation, the deposit’s unique metallurgical features and the future expansion plant that has been designed to optimise recovery of gold.INTRODUCTIONRio Paracatu Mineração (RPM), a wholly owned subsidiary of Kinross Gold Corporation, operates the Paracatu mine. The mine is located in Brazil, 230 km south west of Brasilia in the north west portion of the State of Minas Gerais. The city of Paracatu, which has a population of 83,000 people, is just 2 km south of the mine."

Jan 1, 2007

By Curtis G. Kremer

"New explosives initiation systems continue to be developed as new technologies make advancements possible. Due to recent initiator developments, explosives users now have the most reliable, accurate, safest and easy to use systems ever offered. Three initiation systems recentlyintroduced which offer significant improvement over standard electric and nonelectric initiation systems include Magnadet, EXEL high-strength shock tube, and Redundant two-Dath surface delay systems. These three systems will be discussed zn cecail with rmpiasis on their functioning, safety characteristics, ani specific application areas."

Jan 1, 1991

By Steve Kral

A near-record crowd of mining history enthusiasts made the trip to Leadville, CO in September to attend the National Mining Hall of Fame and Museum’s 19th induction banquet. Dressed in Victorian garb, black tie tuxedos and formal gowns, the 268 people honored four distinguished men who made a lasting impact on the U.S. mining industry. They joined 188 other inductees. The first induction banquet took place in 1988, with about 500 people attending.

Jan 1, 2007

How Particles Stick to Bubbles - The Influence of pH and Hydrophobicity in Flotation

Sep 13, 2010

By C. W. Owings

"Coal may be and has been hauled safely at approximately the same cost with permissible2 storage-battery locomotives as with trolley, cable-reel, crab-reel, or nonpermissible storage-battery locomotives. While in general, thinking mining men readily admit the relative safety of the permissible storage-battery locomotive there are some persons who question the safety of this type; however, the greatest opposition to the widespread use of storage-battery locomotives is from those who believe them to be more expensive to operate and to be more expensive in first cost than the trolley or cable-reel locomotive. Data collected during a comprehensive study- of storage-battery and wired transmission of power in some Pennsylvania and West Virginia coal mines indicate that there is but little difference between the cost of hauling with cable-reel or with storage-battery locomotives. It would appear that if this fact were mere generally known mine operators of the more progressive type would install such equipment and avail themselves of greater safety in hauling coal.The need for greater safety in haulage in coal mines is readily understood when it is considered that during the 12 month period, July 1, 1929 to June 30, 1930, trolley or cable reel gathering locomotives caused four explosions in which 407 lives were endangered, 11 persons were injured, and 30 lives were lost. Still another disaster was averted by the vigilance of a fire boss, who discovered a stratum of gas 3 feet thick at the top of an entry into which a gathering locomotive was about to enter. Other explosions not resulting in any fatality probably have not been reported. In addition numerous fires have been caused by trolley or cable-reel locomotives, and these fires probably would have been avoided had permissible storage-battery locomotives been used."

Nov 1, 1930

By T J. V Duffy, L H. D Siahaan, P G. Albert

G-ResourcesÆ Martabe Mine in North Sumatra, Indonesia, is a US$700 M world-class and world-scale operation in a country which, with a few notable smaller scale exceptions, has had no significant hard rock mining development in more than ten years.The mine was commissioned in the middle part of 2012 and poured first gold on 24 July. At full production Martabe will produce 250 000 oz/a of gold and 2 - 3 Moz/a of silver at cash costs in the lowest quartile. The mine location is on the west coast of North Sumatra, which experiences annual rainfall of 4 m with no notable dry season, adjacent to seismically active fault zones, and relatively close to a rural community of 31 000 people with no significant industrial experience.The management team has successfully forged strong links with the various government departments and levels in Jakarta, North Sumatra Province and the local Regencies; developed long-term relationships with the various community groups within the local district of Batangtoru to build a sustainable social licence; has dealt with the physical and environmental challenges presented by the project location, and has successfully raised more than US$900 M over a period of three years for the original acquisition then the development of the project.Whilst in its infancy of operation, the mine is set up to deliver a long-term sustainable future for the company, the shareholders, and the people of Batangtoru and all stakeholders generally. The quality of the project execution and commitment by the company will ensure that maximum value can be delivered from Martabe, not just for the current mine life but from the significant exploration potential that exists on the large tenement area that the company has access to for 30 plus years.This paper will deal with the physical challenges associated with the design, the Indonesian government regulatory requirements for mine development, the social aspects of building a world-class project in a developing area, the in-country commitment necessary for any project development anywhere in the world and the successful funding arrangements for the mine development.CITATION:Albert, P G, Siahaan, L H D and Duffy, T J V, 2012. Building AsiaÆs latest hard rock mine, in Proceedings International Mine Management 2012, pp 189-204 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

By E. Kamon

This report summarizes completed research pertaining to the reaction of human subjects exposed to Self-Contained Breathing Apparatus (SCBA) stressors during escape conditions (viz., resistance breathing, C02 breathing, hot air breathing, and static positive facepiece positive pressure breathing) and the development of an automated breathing and metabolic simulator (ABMS). Volume I contains summarizes of the studies performed under this contract. Volume II is an appendix which contains more detailed descriptions of these studies.

Jan 1, 1984

In this paper, geostatistical techniques are applied to forecast the annual copper price in the short and medium terms (from one to five years ahead). These techniques allow the incorporation of monthly and multivariate information in the analysis and provide more accurate results than traditional approaches, especially as far as the one-year forecast is concerned. A second advantage of geostatistics stems from its ability to assess the uncertainty associated with the unknown future prices, thanks to estimation variances or confidence intervals, depending on the technique used. Such an assessment has a crucial importance in decision-making, from both macroeconomic and microeconomic points of view

Sep 1, 2004

By A. Cabañas

"In this paper, geostatistical techniques are applied to forecast the annual copper price in the short and medium terms (from one to five years ahead). These techniques allow the incorporation of monthly and multivariate information in the analysis and provide more accurate results than traditional approaches, especially as far as the one-year forecast is concerned.A second advantage of geostatistics stems from its ability to assess the uncertainty associated with the unknown future prices, thanks to estimation variances or confidence intervals, depending on the technique used. Such an assessment has a crucial importance in decision-making, from both macroeconomic and microeconomic points of view. IntroductionThe copper price traded in the London Metal Exchange is a relevant parameter for defining macroeconomic policies of producing countries like Chile. It is also a key factor for the mining companies, since fluctuations in the sell price affect the expected financial flows. Due to the amount of money involved in decision-making, it is necessary to have accurate forecasts of the future copper prices and to quantify the uncertainty associated with such prices.This paper focuses on the annual copper price estimation in the short and medium terms, i.e., from one to five years into the future. Henceforth, the word “estimation” will be used as a synonym of “forecast,” according to the geostatistical jargon (Matheron, 1989).Two main approaches, based either on statistics or econometrics, are currently used to forecast commodity prices, but both of them are not very accurate when applied to copper. First, the main methods are briefly reviewed, then the geostatistical formalism will be presented. So far, the latter approach hardly has been used to estimate commodity prices, although it may reconcile both statistics and econometrics via (1) the use of a stochastic approach and (2) the handling of ancillary variables related to the copper market. Another advantage of geostatistical techniques is the ability not only to forecast the copper price, but also to measure the uncertainty associated with it."

Jan 1, 2004

By Sean Gallagher, Gene Wilson, Christopher Mark, Craig S. Compton, Gregory M. Molinda

Falls of small pieces of rock from between roof bolts continue to cause fatalities and to injure hundreds of coal miners each year. Roof screen is the most effective way to prevent these incidents, but some mines are reluctant to use it because they believe installing screen can be awkward, expensive and time-consuming. The most common type of roof bolting machine used in mines today is the dual boom, outside-controlled roof bolter. Mines who install roof screen using these machines have developed some machine modifications and techniques to ease roof screen installation. This paper describes some successful techniques and machine modifications that are being used in productive mines to assist with roof screen installation. Since the material handling involved with roof screen installation can expose miners to an increased risk of musculoskeletal injuries, the National Institute for Occupational Safety and Health (NIOSH) ergonomists, designed machine modifications and implemented a series of tests to evaluate roof screen handling procedures for outside-controlled, dual boom roof bolting machines. Roof screen installation can also have a positive economic impact on a mine by reducing the cost of injuries, workers’ compensation, required spot or re-bolting, and clean-up of long term travel and belt entries.

By Richard R. Klimpel

During the last 28 years, I have had the very challenging and rewarding experience of working as an engineering professional in a large multinational company, both as a manager of engineers and engineering projects as well as an inventor and generator of new engineering processes and products. Due to the diversified geographic and tech¬nical nature of my employer's business, my responsibilities have taken me all over the world. This has included interactions with people in different industries including minerals, coal, chemicals, petroleum, pulp and paper, agriculture and pharmaceuticals. As diverse as my experience may seem, it has always amazed me how common the basic underlying technology and economic trends are that shape the working environment that any given engineer in any given geographic loca¬tion will experience. I would like to discuss the industrial evolution from micro to macro engineering. One of the basic truths behind how industry must and will operate is "change," including: • the creation of conditions for change, • the anticipation of change, • the resistance to change, • the rewards that being part of a change can bring and • the destruction that change can bring to the unprepared. This fact was well stated by Heractitus around 500 BC.: "There is nothing permanent except change." This simple truth has been valid since the dawn of time and, if anything, is accelerating in nature every decade.

Jan 1, 1993

Common practice in mineral resource estimation consists of partitioning the orebody into several domains defined by grade intervals, prior to the geostatistical modelling and estimation/simulation at unsampled locations. This paper shows the pitfalls of grade domaining through a case study in which we compare the performance of several estimation schemes and demonstrate that the use of domains defined by grade cut-offs implies a deterioration of the resource estimates, mainly in what refers to precision and conditional bias. Then, several conceptual limitations of the grade domaining approach are stressed, in particular the fact that it does not account for the spatial dependency between adjacent domains and for the uncertainty in the domain boundaries. Also, this approach is shown to be sensitive to the cut-offs that define the domains, to provoke artifacts in the kriging maps, histograms and scatter grams between true and estimated grades, and to lower the kriging variance, a feature that may impact the mineral resource classification. An alternative approach is finally proposed to overcome these limitations, based on a stochastic modelling of the grade domains and a co-kriging of the grades using information from all the domains. Keywords: geostatistics, kriging, conditional bias, geological control, grade zoning.

Jan 1, 2005

By H. W. Hunt

Accessories are increasingly used to protect and extend H, pipe, precast concrete, timber, and sheet piles for any soils conditions. With point protection, piles can be driven through boulders, layered rock, garbage dumps, and waterfront debris to provide dependable support for all types of structures. Splicers for pipe piles can be tapered for a water-tight drive-fit that does not require welding. The pipe splicer can be made applicable to precast concrete piles. Splicers for H make the long pile as strong as an unspliced length with only simple welding. Transition splicers quickly connect different types or sizes into efficient composite piles.

Jan 1, 2010

By J. D. Stone

This paper briefly reviews the adequacy of existing management theories and practices and the managerial proficiency or competency in the South African mining industry. The investigation revealed that existing management practices are totally inadequate to enable all employees on all the levels of the mining industry to achieve the results required from them, in all aspects, at all times. As a result, the South African mining industry is gradually losing its long standing reputation as a relative cheap, competitive, and reliable supplier of minerals to the local and global markets. According to some prominent management authors and theorists, an all-inclusive unified management theory does not exist at present. In this paper the authors summarize the main aspects of a newly developed comprehensive, practical, and integrated management method. It is believed that the application of this method would significantly improve the future performance and competitiveness of the South African mining industry

Jan 1, 2010

By Donald P. Richards

Is a shaft the same as a tunnel and can it be approached in the same manner for design and construction? The most obvious difference between a shaft and a tunnel is that of orientation; whereas a tunnel is commonly near horizontal or slightly dipping, a shaft is commonly vertical or steeply inclined. As a result, design and construction methods employed for tunneling, in general, cannot be directly applied to shafts, although some of the basic concepts of behavior are quite similar. Many of the shafts that have been sunk in various parts of the world are owned by private mining companies. Each company has generally accumulated years of experience in shaft sinking and mining techniques pertinent to its particular geographic location. When a new shaft is to be sunk or an existing shaft deepened, the tendency often seems to be to continue to use the methods that have been used successfully in the past.

Jan 1, 1979

By Daniel C. Boteler

Five lignites from the northern Great Plains province were carbonized at temperatures from 500° to 1,000° C in a bench-scale unit. A replicated Greco-Latin square experimental design was employed to allow testing of four independent variables at five levels. Independent variables investigated were temperature, source of lignite (mine), weight of charge, and moisture content of charge. Dependent variables were char yield, tar yield, light-oil yield, tar plus light-oil yield, carbonization gas yield, and carbonization gas heat yield. An analysis of variance indicated that, at the 99-percent confidence level, the independent variables of carbonization temperature, source of lignite, and weight of charge were significant for yields of char, tar plus light oil, and carbonization gas, whereas moisture content was only significant for carbonization gas yields. At the 95-percent confidence level, moisture content significantly influenced the carbonization gas heat yield per pound of lignite charge and the yields of dry tar plus light oil. All dependent variables were determined on a moisture- and ash-free basis. Multiple regression equations for predicting seven different factors of carbonization yields as functions of carbonization temperature and initial composition were developed using computer techniques. Equations for yields of char, tar plus light oil, and carbonization gas were compared with equations previously developed by others at the 500° C level.

Jan 1, 1970

By P. Oyanader

"In 2001, the Catholic University of Chile undertook a maintenance benchmarking study of six open pit copper mines having mill capacities varying between 18,000 t/d and 156,000 t/d, and collectively responsible for 58% of Chilean copper production. This paper describes the methodology used to conduct the study, as well as the overall results. Key performance indices were selected to measure the effectiveness, efficiency, and development of the maintenance process. Using a balanced scorecard philosophy, these indicators were divided into client satisfaction, financial, internal process, and learning and growth indices.Maintenance was found, on average, to be responsible for 44% of mine production costs. Percentage planned maintenance of equipment fleets was found to be low by world standards, averaging 35%, 56%, and 44%, respectively, for blasthole drill, shovel, and haul truck fleets. Fleet availabilities were found to be significantly influenced by the percentage of planned maintenance achieved, while maintenance cost per equipment was found to decrease non-linearly with increases in percentage planned maintenance. Investment in technical training (including planned maintenance practice) was found to be low by global standards. The paper concludes that fleet availability and maintenance costs in Chilean open pit operations could be considerably improved by improving and/or developing maintenance planning standards, and investing in training personnel in planned maintenance techniques"

Jan 1, 2005