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By M. J. Scoble, L. M. Daneshmend, C. Hendricks

Paper presented at a meeting on: Artificial intelligence in the minerals sector, held in Nottingham, UK, 20 April 1993. An attempt is made to relate emerging technologies to education and training requirements by examining the nature of the Canadian mining industry's human resources. Particular attention is given to the trends evident in mine automation and their likely impact on instructional needs. The characteristics of "computer-aided instruction" systems are reviewed and related to the implementation and support of mine-wide monitoring and communication networks, which are seen as fundamental to the eventual automation of underground hardrock mines

Apr 1, 1994

The spatial distribution of copper grades at the Mansa Mina project is highly variable due to the presence of high grade copper/silver/arsenic breccia bodies. Copper grades within the breccia bodies tend to average about 4.5% copper while grades in the surrounding stockwork average about 1.0%. The breccia is known to occur in the vicinity of significant controlling structures, however, the outline and therefore the thickness of the bodies are far from regular. Due to the high grade of these bodies a significant proportion of the value of the project is derived from the breccia tonnages. The irregularity in the outlines/thickness translates into an uncertainty in the breccia tonnage and therefore in the value of the project. Acknowledging the economic importance of the breccia bodies and the risk associated with the breccia tonnage uncertainty, significant additional drilling has been proposed to both understand the spatial distribution of the breccias and reduce project risk. The costs associated with this additional drilling are not inconsequential; thus, a reasonable question is ‘what value is derived from this additional drilling’? To obtain an answer to this important question, a simulation approach is applied. First the deposit is simulated using the existing drilling and the uncertainty in the resource is defined. Next the proposed drilling program is simulated and the simulated data are added to the existing data. Using this expanded data set a second simulation of the deposit is created and once again the uncertainty in the resource is defined. Using this approach, the reduction in the uncertainty in the resource can be determined. To convert this reduction in uncertainty (or reduction in risk) in the stated resource into a dollar value, a method of defining the increase in the project rate of return necessary to account for risk is presented. Using the two different rates of return, the difference in project NPV and hence the value of additional drilling is determined.

Jan 1, 2003

By Andrew K. hg` Officer, A. L. Griffiths, J. Andrew Hindmarch, Gert Wittneben

Durban Harbour in South Africa is one of the continent’s busiest ports however the harbor entrance is currently too small for the new generation of container ships. There-fore it is to be deepened and widened by the National Ports Authority in the near future. An existing immersed tube tunnel carrying major sewer, water and other utilities under the harbor first needs to be removed and replaced by a deeper 4.4 m ID ser-vices tunnel. Construction of the deeper tunnel saw the first use of a slurry machine in South Africa and was required to negotiate grades up to 20%.

Jan 1, 2007

By Derek J. Penrice

The Caltrain Downtown Extension (DTX) project will extend commuter and future statewide high-speed rail service into the Transbay Transit Center, which will be located in the business district in downtown San Francisco. The DTX project includes 1.5 miles of underground construction, comprising complex sections of mined and cut-and-cover tunnel. As part of the DTX preliminary engineering process, development of appropriate contracting practices, including contract packaging, procurement methods and contract terms for the underground construction, has been initiated. This paper provides a summary of the evaluations undertaken, preliminary conclusions reached, and proposed next steps to promote industry interest and maximize bid competition.

By Susanne Hering, Brent Kirby, Charles D. Litton, Tracy Allen, Kirk R. Smith, Rufus Edwards

In developing countries, high levels of particle pollution from the use of coal and biomass fuels for household cooking and heating are a major cause of ill health and premature mortality. The cost and complexity of existing monitoring equipment, combined with the need to sample many locations, make routine quantification of household particle pollution levels difficult. Recent advances in technology, however, have enabled the development of a small, portable, data-logging particle monitor modified from commercial smoke alarm technology that can meet the needs of surveys in the developing world at reasonable cost. Laboratory comparisons of a prototype particle monitor developed at the University of California at Berkeley (UCB) with gravimetric filters, a tapered element oscillating microbalance, and a TSI DustTrak to quantify the UCB particle monitor response as a function of both concentration and particle size and to examine sensor response in relation to changes in temperature, relative humidity, and elevation are presented here. UCB particle monitors showed good linearity in response to different concentrations of laboratory-generated oleic acid aerosols with a coarse (mass median diameter, 2.1 µm) and fine (mass median diameter, 0.27-0.42 µm) size distributions (average r2 = 0.997 ± 0.005). The photoelectric and ionization chamber showed a wide range of responses based on particle size and, thus, require calibration with the aerosol of interest. The ionization chamber was five times more sensitive to fine rather than coarse particles, whereas the photoelectric chamber was five times more sensitive to coarse than fine. The ratio of the response between the two sensors has the potential for mass calibration of individual data points based on estimated parameters of the size distribution. The results demonstrate the significant potential of this monitor, which will facilitate the evaluation of interventions (improved fuels, stoves, and ventilation) on indoor air pollution levels and research on the impacts of indoor particle levels on health in developing countries.

Although not fully accepted in South Africa, the Theory of Sampling originally proposed by Pierre Gy is fast becoming the cornerstone of sampling practice throughout the world. The growing acceptance of Gy?s Theory of Sampling in South Africa can be attributed to a number of factors, chief amongst them being the development of a tradable mineral asset market, the promulgation of the Mineral and Petroleum Resources Development Act (MPRDA), the growing number of commercial and academic courses that are offered on sampling, and the regulation of the industry through internationally acceptable guidelines and rules for reporting and trading in mineral assets. The size of the South African minerals industry and the dependence of our economy on mineral production have also meant that correct sampling is of key importance to mineral trade. ISO standards have been the principal guides for producers of mineral bulk commodities who produce to customers? specifications, whereas Gy?s insights have been most readily accepted by precious and base metals producers whose product is sold into metal markets. Understanding of small-scale variability is essential in the precious and base-metal industries, but detailed studies of the effects of heterogeneity have not been as productive in the bulk commodities. Sampling practices at different stages of mineral development from exploration, face sampling and grade control, ore processing and handling, metallurgical sub-sampling, point of sale sampling, and sampling in the laboratory are considered in the gold, platinum, ferrous metal, and coal industries. A summary of the impact of poor sampling in these industries is presented. Generally it appears that poor sampling practice is most likely to erode mineral asset value at the early stages of mineral development. The benefits of good sampling are considered, especially with regard to the financial implications of bias and error on large and consistent consignments of bulk commodities. Keywords theory of sampling, sampling errors, ISO standards.

Jan 1, 2014

By John C. Machisak

DATA ON INJURY experience at quarries and related plants of the United States are presented in this publication under the following general sections: A) General injury experience: Tables 1-4: Contain current data on number of injuries, injury-frequency rates, work location, accident agency, degree of injury, and related employment data. (B) Injury experience at different kinds of quarries: Tables 5-6: Current data on number of injuries, injury-frequency rates, work location, accident agency, degree of injury, and related employment data. (C) Injury experience by States: Tables 7-19: Current data on the number of injuries, injury-frequency rates, accident agency, degree of injury, and related employment data. (D) Selected injury data: Tables 20-30: Current data on various selected factors of operating conditions at different kinds of quarries, including employment size-groups, length of shifts, comparative severity of injuries, and injury data and related employment experience at dimension-stone and crushed and broken stone quarries, and underground quarries. (E) Mining methods and historical injury experience: Tables 31-32; Employment data and injury experience in the quarrying industries of the United States, by mining method and work location, 1953-58; and historical injury experience and employment data in the quarrying industry, 1911-58.

Jan 1, 1962

By H. S. Price, J. C. Cavendish, R. S. Varga

A numerical formulation of bigh-order accuracy, based on variational methods, is proposed for the solution of multidimensional diffusion-convection-type equations. Accurate solutions are obtained without the difficulties that standard finite difference approximations present. In addition, tests show that accurate solutions of a one-dimensional problem can be obtained in the neighborhood of a sharp front without the need for a large number of calculations for the entire region of interest. Results using these variational methods are compared with several standard finite difference approximations and with a technique based on the method of characteristics. The variational methods are shown to yield higher accuracies in less computer time. Finally, it is indicated how one can use these attractive features of the variational methods for solving miscible displacement problems in two dimensions. INTRODUCTION The problem of finding suitable numerical approximations for equations describing the transport of heat or mass by diffusion and convection simultaneously has been of interest for some time. Equations of this type, which will be called diffusionconvection equations, arise in describing many diverse physical processes. Of particular interest here is the equation describing the process by which one miscible liquid displaces another liquid in a one-dimensional porous medium. The behavior of such a system is described by the following parabolic partial differential equation:

Jan 1, 1969

By Jim Owens

The methodology of quarrying changed significantly in the Indiana limestone industry in the 60 years between Sept. 11, 1941 and Sept. 11, 2001. The former was the date of the Pentagon groundbreaking ceremony, while the latter was when the building was damaged by American Airlines Flight 77. So too, though to a lesser degree, did the machinery and methods used to fabricate the stone. The rededication ceremony on Sept. 11, 2002 marked the end of the Phoenix Project, as the rebuilding effort was named. The story of this remarkable project illustrates what the American construction(and Indiana limestone) industry can accomplish when working toward a common goal.

Jan 1, 2005

By D. C. Kaliampakos, A. K. Moutsatsou, J. K. Skotaras

The wastes from marble extraction in the Thasos- Kavalla-Drama region of northeastern Greece could be utilised as a new source of high-quality white carbonate fillers for the European market. Large deposits, satisfactory properties, acceptable processing costs and environmental benefits are among the factors that would have a positive bearing on a proposal for their use in this way. DTH, the waste arising from dolomitic marble quarrying operations on the island of Thasos, appears to be the more suitable material than DA waste from Nikissiani on the mainland because of the lower cost of primary grinding and the higher production rate of ultrafines with a mean particle size of 5 micrometres (the optimum size for filler properties in the case of both DTH and DA), its superior whiteness, the benefits that such use would bring to a very severe and complex environmental problem and the lower transport cost

Jun 18, 1905

By Kennedy G. L

Experience is reporled in the operation of the pilot Lurgi carbonization plant at Morwell, afler it had been reconstructed to obtain better control of the heating of the briquettes in order to produce a strong char suitable for use as a metallurgical fuel. The theoretical Ideal Heating Cycle, which had been designed from earlier laboratory research, was closely approached in the carbonizer, and up to 97 per cent of the whole dried briquettes entering the carbonizer were recovered unbroken in the char.The strength of the char produced in the pilot plant was limited by the performance of the drier where the cracking and breakage of the briquettes was more severe. Theoretical studies have indicated that this limitation could be removed by using a hot briquette feed to the pilot plant. Experience indicates that with a hot briquette feed to the drier and with ideal heating in the carbonizer, hard char could be produced from Yallourn briquettes in continuous operation.The project has been terminated for economic reasons...

Jan 1, 1966

By Eric Bain Wasmund, Lance Christodoulou, Julio Jairo Carmona Franco, María Fernanda Castillo, Jose Concha

"A number of technologies are in practice for selectively removing coarse gold from conventional grinding circuits. These circuits are often designed so that the grinding mill output is size classified, with large (or high density) particles being removed before the tails are returned to the mill. Because of the high relative SG of gold, and the fact that some forms of gold such as free gold do not break apart during conventional grinding, coarse gold can accumulate in the circulating load, and eventually be lost.Eriez has developed a flotation cell that uses fluidized water to enhance flotation of coarse particles. More than 40 units have been sold in industrial minerals, and we are now exploring applications for the HydroFloat® in the gold industry.Mineros S.A currently produces approximately 120,000 oz of gold per year by gravity concentrating alluvial gold ore with a mean particle size of 330 microns, followed by further concentration using a Falcon separator. A 400 mm diameter pilot-scale HydroFloat® was added to the tails of the Falcon to test whether additional gold could be captured. Enrichments of 50-600 times and recoveries normally in excess of 95% were achieved. This allowed direct smelting of the gold concentrate. Metallurgical results and operating parameters such as water addition and power will be discussed during the presentation.This result opens the possibility that the HydroFloat® could be used directly in the grinding circuit, for removing coarse gold in the circulating load. This work also shows the possibility that the HydroFloat® can produce a throwaway tail, which will reduce the size of the circulating load stream and the grinding requirements of the circuit."

Jan 1, 2015

By Dean E. Matthews

The concept of a pile for construction is credited to a Neolithic tribe called the "Swiss Lake Dwellers" who lived in what is now Switzerland about 6,000 years ago. They used piling, not for supporting heavy loads as we do today, but for elevation to protect themselves from wildlife. The Romans often used piles, and built many structures, including buildings, homes, bridges, roads and viaducts on piling. The Romans built the first bridge across the Tiber River in Rome on timber piles in B.C. 1620. Homes in the cities of Venice and Ravenna were built on piles from B.C. 100 to A.D. 400. The Romans also built the first bridge across the Thames River in London in A.D. 60 on timber piling.

Jan 1, 2003

By Cadman S. J

( The central part of the Gippsland Basin is surrounded by existing major Petroleum accumulations and although six exploration wells have been drilled in the area, none are significant petroleum discoveries. Post drilling analyses indicate that the wells were drilled off structure due to the presence of high-velocity Miocene channels. These channels contain carbonates of significantly higher interval velocity than the surrounding sediments. Problems with seismic interpretation were thus encountered in the development of prospects in the central part of the Gippsland Basin as part of a BMR prospectivity study. The seismic interpretation problems associated with the Miocene channels are two-way time pull-ups at the underlying top of Latrobe Group and deeper levels on the seismic sections. Interpreted seismic sections passing through some of the exploration wells and the Miocene channels are presented to illustrate the configurations of these channels and the pullup effect associated with them. Two different methods of depth conversion were applied, one for the area below the high velocity channels and the other for the area away from the channel. The application of these two methods of depth conversion were found to be reasonably successful in correcting for the pull-ups caused by the high velocity Miocene channels. Mapping of the events near the top of Latrobe Group and near Base Lower L balmei seismic horizons has led to the identification of several potential structural closures. Further exploration efforts are necessary in this area to test these closures.

Jan 1, 1992

It has long been recognised that Australia can benefit substantially in an economic sense from its rich resource base. The significant resources of the Gippsland Basin are a good example of the wealth of this nation. As cited in popular debate, Australia must value-add to its natural resources to ensure its long term economic prosperity. The significant oil, gas and coal resources of the Gippsland Basin have provided the Strategic Research Foundation with the basis for two major research and development initiatives ensuring the long term economic development of the Basin and Australia. The gas and coal reserves of the Basin together with the area's extensive history in electricity generation provide the rationale for establishing Ceramic Fuel Cells Ltd. A consortium comprising Australia's leading industrialist - BHP, State energy authorities and the Nation's major research and development organisations, has formed Ceramic Fuel Cells to undertake and manage research, development and commercialisation of solid oxide (ceramic) fuel cells which convert fossil fuels directly to electricity with greater efficiency and less pollution than existing technologies. The oil and gas resources of the Basin together with the valuable experience of the operators in recovering these resources, have provided the impetus to investigate the feasibility of a Marine Engineering Research Centre. The commercially oriented research, education and training objectives of the Centre are well supported by the leading industrialists in related industries.

Jan 1, 1992

By Leon del Valle, Joe Phillips

First, I want to thank my co-author, Leon del Valle for his help and collaboration in the preparation of this paper, and also ORICA S.S. our explosive supplier and contractor at the Refugio mine site for their collaboration. The Southern Andes Mountains present a number of challenges for mining operations, and associated blasting operations. This region of the world, in Peru, Bolivis, Chile and Argentina is an area of rapid growth in precious and base metal mining, and will continue to be a large growth area for explosives products and services. This paper will attemp to discuss some of the special considerations encountered in operating a safe and effective blasting program at high elevation and under extreme weather conditions, as well as outlining a recent improvement in blasting techniques at the Refugio gold mine in northern Chile. This paper is presented from a mine operator's perspective, which may be a bit of a disappointment for some of you interested in a detailed technical review of our program. It willl, however, provide an insight in how in-pit blasting techniques tie into the metallurgical processes at a modern precious metal mine and thereby become a key elemnet in its success.

Jan 1, 2000

By J. Torma-Krajewski, C. Hipes

Although many mining companies apply ergonomic principles, it is usually done either informally and/or reactively. An example of an informal approach is replacing worn equipment (such as seats) with models that have ergonomic features. Another example is modifying a task to eliminate safety hazards. Such approaches reduce risk-factor exposures that can lead to musculoskeletal disorders (MSDs). A reactive approach is followed when modifying a task/ equipment after an MSD occurs. However, neither of these approaches involves a systematic method of proactively applying ergonomic principles to actually prevent injuries or illnesses. This paper discusses how Vulcan Materials Company applied ergonomic principles and implemented interventions to reduce risk-factor exposures.

By Damon C. Gray

This report contains a recommended program of acoustic research to be conducted by the U. S. Bureau of Mines. The program is directed toward the abatement and control of machinery noise in underground coal mining operations. The study conclusions and specific problem areas which led to the definition of the recommended program are also briefly described.

Jan 1, 1971

By Ivan B. Cutler, Milton E. Wadsworth

Coprecipitation of anionic and cationic polyelectrolytes has been applied to floccula-tion of several mineral systems. Results obtained in a study of the flocculation of kaolinite and hematite suspensions of polycationic and polyanionic electrolytes are presented. Greatly increased settling rates were observed following precipitation of positive and negative polyelectrolytes on the surface of finely divided minerals in aqueous suspension. The ratios of polycationic to polyanionic electrolytes required to produce maximum sedimentation have been shown to correspond closely with the equivalence points obtained by light scattering studies of systems containing the positive and negative polyelectrolytes by themselves. DISPERSION of colloids has been of interest to surface chemists for many years. Flocculation studies have been employed to evaluate the limits of colloid stability. In water suspensions, colloids become unstable and flocculate when the 5 potential, the potential of the kinetic solvation sheath, falls to a value at which van der Waals forces may act to draw the particles together. This may happen through an adjustment of the pH of the suspension or by addition of a salt. Optimum conditions for rapid formation of large flocs are found in the region of minimum < potential. In addition to these well known considerations, colloids in water suspensions are known to be flocculated by certain large organic macromolecules. These polyelectrolytes in some cases minimize the 5 potential and in other instances increase the attractive forces by supplying sites for hydrogen bonding.&apos; Use of organic polyelectrolytes in flocculation of mineral colloids has increased rapidly in recent years. These materials are now recognized as indispensable aids to fluid-solid separations in many extractive metallurgical operations. They have been found to increase both the settling rate in thickeners and the filtration rate of filters. In the elucidation of the characteristics of these organic reagents as floc-culants in this laboratory, it was discovered that interaction of certain polyelectrolytes had a surprisingly good effect on flocculation of mineral colloids. Experimental Procedure: The anionic flocculants used in this study were Lytron 886 and 887, produced by Monsanto Chemical Co. Both reagents are copolymers of vinyl acetate and maleic anhydride. Lime is added to Lytron 886, whereas Lytron 887 is all organic. These reagents possess two carboxyl groups for each acetate group and are therefore anionic in character. The cationic reagents used were the Peter Cooper Co. 1-X and 2-X glues. The structures are not definitely known, but the re- agents are amines and are cationic in character. The glues were prepared in the chrome-alum form. Both types of reagents may be classified as polyelectrolytes in that they are high molecular weight polymers and ionize in water. All data presented are in terms of sedimentation rate, measured in 250-ml glass-stoppered graduated cylinders. With suitable precautions such measurements are fairly reproducible and provide a sensitive means for selecting important parameters such as PH, reagent concentration, and floc size and density. Agitation was standardized with five complete end over end cycles of the suspensions in the stoppered graduated cylinders.

Jan 1, 1957

Various influences determine how an Environmental Management System (EMS) for a mining or petroleum project is developed and administered. These influences include the environmental and resource legislation applying to the project, the culture of the organisation, the environmental sensitivity of the area, and the administrative policies of the regulatory agencies involved. While financial penalties and even imprisonment may be imposed for non-compliance with environmental legislation, there are other compelling reasons for the establishment of an effective EMS. If a company wishes to be considered by Governments for the grant of exploration or mining rights, it is important that it can demonstrate environmentally responsible operations at existing facilities. The development of an effective EMS requires commitment from the Board of the company and the issue of an Environmental Policy to empower all levels of the staff and workforce to achieve environmentally responsible operations. This must be supported by the provision of appropriate human and financial resources, and environmental training of staff at all levels from the Board to the mine site, workshop and office. A regular environmental auditing programme is essential to ensure that the EMS is in place and is effective in achieving compliance with regulatory requirements, corporate policies and protection of the environment. An EMS can be developed on the basis of existing management systems, quality management systems, existing and emerging environmental management standards (such as BS7750 and ISOI4000), or sophisticated computerised systems which may incorporate international experience, standards, and codes of practice.

Jan 1, 1995