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By F. Soumis

This paper describes an integrated procedure for the very short term production planning of an open pit and the execution of this plan: the truck dispatching. Integration of plan and dispatch means that the plan is realistic so that its objectives can be realized by the dispatch. This realism is obtained by supplying the plan optimization, which involves mixed integer programming, linear programming and non-linear programming, with experimental O.R. models of waiting and blending. The arrangement of these models in the computer programm has made it possible to obtain very short computing time for the planning in spite of the width of the optimisation. The dispatching of a truck is made by solving a classical assignment problem for each dispatch over a horizon of the expected*next 10-15 trucks to request dispatches. This deep-reaching dispatch procedure uses the continuously arriving information about trucks' positions and shovels situations and models by probability functions the expected waiting time of shovels and trucks. In this manner trucks and shovels are synchronized and last moments' opportunities for productivity gains can be obtained. The dispatch procedure takes .5 second on PDP11. This integrated planning and dispatch procedure gives high productivity while ensuring good blending. Results from the Mount Wright mine of the Quebec-Cartier Mining Co., where the integrated procedure has been installed on the existing computer equipment PDP11, are included.

Jan 1, 1989

By R. Matikainen

Since the Brundtland Commission in 1987, the use of natural resources has been an issue of global concern. Minerals are among the most important Earth resources and will definitely be essential for the development of societies also in future. Increasing scientific effort is needed not only to discover new deposits, but also to promote resource management in ecologically and socially sound way. Sustainable resource management is essentially a multidisciplinary challenge of developing life-cycle analysis and recycling of non-renewable resources from local to global scale. It offers great opportunities for geological surveys not only in EU, but all over the world to contribute positively to the welfare and sustainability of societies.

Jan 1, 2003

By Douglas Owen

Two case studies describe the introduction of technology new to an organisation. The lessons learnt from these Case studies contribute to Our general understanding of the management of technological change.

Jan 1, 1989

By Donald P. Richards, David W. Campo, Michel Coudry

This paper presents a review of the grouting works of Line 2 of the Greater Cairo MetroSystem. The Nile River alluvial deposits underlying this ancient city provided for a challenging and sometimes difficult grouting project. Permeation grouting using state-of-the-art computerized grouting techniques, as well as extensive ground treatment by jet grout, was per-formed for soil consolidation and/or groundwater control. During the project, over 425,000m3 of ground was treated, requiring 1.4 million linear meters of drilling and PVC injection pipe, 54,000 m3 of bentonite cement and 230,000 m3 of chemical and mineral grout. In addition, over 70,000 m3 of ground was treated using the jet grout method. Relative to major international transportation projects, the grouting works for Line 2 of the Cairo Metro represent one of the largest worldwide grouting endeavors to date.

Jan 1, 1997

By Alfred Weiss, Andrew E. Nevin, Thomas J. Neil, O&apos

As Edward E. Runyan, 1983 AIME President, in an interview excerpt in ME, June, p. 607, stated, "...the AIME Transition Committee has recom¬mended to the AIME Board that each Constituent Society be allowed the option of separate incorporation, whereby each could become its own separate legal entity." Background The American Institute of Mining Engineers (AIME) was formed in 1871 by 22 engineers in Wilkes-Barre, PA. Although originally a mining organization, it became a home for metallurgists, iron and steel industry people, and for the individuals in the expanding petroleum engineering profession. There are now four Constituent Societies: Society of Mining Engineers, located in Littleton, CO, 29,000 members; Society of Petroleum Engineers, located in Dallas, TX, 47,500 members; The Metallurgical Society, located in Warrendale, PA, 10,000 members; and Iron and Steel Society, located in Warrendale, PA, 6,500 members. Each of the four groups has grown and continues to serve the specific and/or diverse needs of its membership. As the needs and requirements of their industries and professions change, each of the Societies has perceived and initiated programs that serve their constituency rather than AIME as a whole. Therefore, each Society has recognized an increasing need for autonomy to better augment their own programs. An AIME Ad Hoc Transition Committee, with Robert Merrill, AIME Past President, as chairman, made a number of recommendations pertaining to AIME operations that were approved in October 1982 by the AIME Board of Directors. One of the recommendations was to endorse separate incorporation of the Constituent Societies on an individual-society-option basis. The AIME Board commissioned a task force of Constituent Society representatives to develop specific revisions to the AIME Certificate of Incorporation and the AIME Constitution and Bylaws. This was done to allow separate incorporation and to reflect the decentralized structure of the Institute. The SME-AIME Board of Directors subsequently approved the recommendation of SME Working Party #69 that SME pursue separate incorporation. Meanwhile, Working Party #69 continues to work with the other Constituent Societies and with the AIME Task Force on Reorganization to determine the form and substance of the separate incorporation. Why Incorporate? George Webster in The Law of Associations quoted Chief Justice Marshall's (1819) definition of corporation as: "A corporation is an artificial being, invisible, intangible, and existing only in contemplation of law. Being the mere creature of law, it possesses only those properties which the charter of its creation confers upon it, either expressly or as incidental to its very existence. These are such as are supposed best calculated to effect the object for which it was created." SME-AIME attorneys, Davis, Graham & Stubbs, have pointed out that the status of an organization operating as an unincorporated association is always unclear. At present, SME-AIME administers assets of almost $3.5 million (mainly property and inventory) but technical ownership and ability to enter into contractual relationships resides with AIME. However, the operation appears to outsiders (particularly those with whom SME-AIME does business) to be an independent operation which would be expected to be a legal entity in its own right. Advantages of Incorporation Liability. Because of legal ownership by AIME of all assets of the Constituent Societies, those assets are subject to the claims of any of the creditors of AIME or any of its constituent parts (i.e., the other societies). Liabilities can be those usually encountered in business but also encompass special risks, which could develop if there were a careless and erroneous publication of material that might be used in practice or if standards are improperly established. The recent US Supreme Court decision in American Society of Mechanical Engineers, Inc.,

Jan 10, 1983

By Krystyna Raszka, Jerzy Iskra

The paper presents results of spectrophotometric investigations concerning the adsorption of sodium oleate on silicon carbide in the presence of the cations of multivalent metals, applying the ATR IR technique with computer-aidedprocessing of the spectrum. The analysis of these spectra indicates the occurance of distinct OH and COOH bands in the pH range in which the hydroxy complexes of metals of the type MeOH+ and MeOH++ reach in the respective cases the highest concentration in the solution. The correlation of these results with those of flotation, measurements of the zeta potential confirms the proposed mechanism of activation of the flotation of silicon carbide, applying sodium oleate as a collector, the collection taking place over the adsorption of hydroxy complexes of the type MeOH+ and MeOH++

Jan 1, 1995

By R. J. McGregor

The Internet has revolutionized worldwide communications. Any real or perceived mining incident or environmental spill, no matter how small or remote, can become a disaster of "biblical proportions" through the judicious use of the Internet by environmental and anti-mining groups. In addition, mining companies' own Web sites and unofficial message boards can provide plenty of additional ammunition to the anti-mining forces. This paper explores how the Internet and readily available information are used by anti-mining groups active on the Web.

Jan 1, 2001

By Edward M. Belsky

Increasingly stringent government environmental regulations will affect the availability and costs of bonding and insurance products for the mining community. New regulations requiring Environmental Impairment Insurance, Reclamation Bonds, and Cyanide Use Bonds will result in both an increase in cost and a decrease in availability of affordable insurance and bonding pro- ducts. Professional Liability Insurance for engineers that covers pollution exposures will be a must for all professional engineers working in the mining community. By understanding the problem, solutions can be structured to allow your company to obtain the mandated insurance at the most favorable cost and conditions!

Jan 1, 1991

By Arthur F. Moss

Smallbore tunnels in urban environments often present more technical and managerial problems than major large diameter schemes carried out for transportion, water supply and hydro-electric facilities. The 1.8 km Bath scheme was designed for construction in tunnel using the pipe jacking system. Unforeseen ground conditions meant other techniques were needed during construction. The paper describes the problems encountered and how they were overcome.

Jan 1, 1981

By Po-Wei Tun, Kuen-Yuh Wu, Tso-Min Shih, Hsi-Chiang Fang

The purpose of this study is to investgate the coal dust explosion characteristics and to search for the prevention methods of the coal dust explosion as well as the propagation of the explosion flame of the middle-bearing coal formation in Taiwan by an open type coal dust explosion apparatus in laboratory. The coal samples were taken from the typical middle-bearing formations of the Sam-Ming,Tai-Ho and Lee-Fong coal mines The rock dusts, the free water mixture with coal dust samples and the interval clean out the coal dust in the testing chambers were applied for preventing the coal dust explosion and the propagation of the explosion flame.

Jan 1, 1993

By Gary Johnson, Bill Mackenzie

The Paddy's Flat plant of Dominion Mining Limited was commissioned in March 1988 with a design throughput rate of 700,000 tpa. The plant now treats ore at an annualised rate of over 2,000,000 tpa. The only major capital improvement to the plant has been the addition of a pebble crushing circuit. Whilst significant changes in the average hardness of the ore being fed to the plant have obviously occurred, a number of processing innovations have been necessary to enable these throughputs to be maintained. The treatment of ore types with a wide variety of physical properties has been a feature of the operation of the Paddy's Flat plant. The leaching characteristics of the ores are relatively straight forward, and it has been possible to considerably enhance the rate of gold extraction from the ore. Reserves of soft surface ore have been increased which has created the opportunity to improve the profitability of the operation by increasing throughput to considerably above the design level, without having to increase the capital investment in the plant.

Jan 1, 1992

By Richard Ladyman, Ken Baxter, G. B. Siddall

The IPS process, developed by Baxter and McAuley, was first applied in Australia in 1984 at Browns Creek in NSW where a small 300kg batch plant was in operation for a number of years. To date a further 14 plants have been installed. While a number of engineering companies have engineered applications of the technology, a majority of the plants constructed to date have been constructed by Como Engineers who have a reference list of 9 installations with batch capacities up to 3.0 t.

Jan 1, 1996

By Robert Stauffer, John Frostiak, Rein Raudsepp

Placer Dome's Campbell Red Lake Mine in Balmertown, Ontario produces a refractory gold flotation concentrate containing the sulphide minerals arsenopyrite, pyrite and pyrrhotite. In 1991, the existing concentrate roasters will be replaced with a pressure oxidation plant based on Sherritt Gordon technology to update the facilities and to satisfy environmental requirements. A successful continuous pressure oxidation miniplant program was conducted by Sherrill Gordon in late 1989 which formed the basis for the design of the commercial plant. The paper summarizes the Campbell operation and the environmental aspects of the project, and discusses the results of the miniplant program and the design of the commercial plant. The capital cost of the pressure oxidation plant and the process operating costs are also presented.

Jan 1, 1990

By J. D. Christensen

In August 1987, we marked the tenth anniversary of the Surface Mining Control and Reclamation Act. Anniversaries are supposed to be times of celebration, and I truly believe that we have something to celebrate on this anniversary. For, after ten years, there has been much progress in the implementation of the surface mining law.

Jan 1, 1988

By Ken Takahashi, Yuuich Umeki, Masahiko Arakawa, Dr. Tominaga. Yuusaku

Macroscopic characteristics of a complicated mine ventilation is remarked to build an expert system for mine safety in the Taiheiyo coal mine, Hokkaido, Japan. To gain the characteristics a large number of simulation were performed with varying aerodynamic resistance of the branches with regulator in mine ventilation network. The principal results of the study are as follows, (1) Pressure loss diagram for ventilation network with main and auxiliary fans enables capability of air circulation in the network. (2) H-Q (pressure-quantity) diagram gives capacity of air quantity In a network with main and auxiliary fans. (3) When airflow rate, [] through branch qi is changed by opening/closing regulator set in the branch, air flow rate, [], through branch p can be represented by the empirical formula. [ ] where Api and Qp,o are the constant coefficients. (4) Macroscopic characteristics mentioned above are available to make rules in an expert system for escaping route at emergency.

Jan 1, 1989

By Simon D. Strauss

This paper discusses the ways in which the metals industries dealt with surplus capacity in the past, primarily the twenty years, 1950 - 1970. During this period, the bulk of metals production in the market-economy countries was controlled by private sector companies. Since then, public sector companies have played an increasingly important role in the metals industries of the market-economy countries. Of course, the change was not overnight. It occurred gradually over a period of many years. Indeed, by 1965, several developing nations had adopted policies of government control of metal operations previously in private hands. The metals industries are so many, so large and so diverse that the constraints of time make it impossible to deal with all segments. To illustrate the problems of surplus capacity in the metals industries during the period, this paper focusses primarily on three metals. One experienced rapid market expansion between 1950 and 1970; one had a growth more or less in line with the expansion of the world economy; and one lagged well behind the pace of industrial expansion. No one will be surprised if aluminum is identified as the metal with rapid growth; copper is identified as the metal that kept pace with the world economy; and tin is identified as the laggard. Individual computations of the rate of growth for these metals show some variations, but most estimates place the increase in aluminum consumption in the market economy countries between 1950 and 1970 at a compound annual rate of about 8%. The corresponding figure for copper is a compound rate of 4%. Tin consumption showed no growth. A widely accepted point of view is that sharply rising demand will force the price of a commodity to increase substantially in order to attract a necessary expansion of supply. The corollary to this is that stagnant demand will hold prices down, as there is no need to stimulate new supply and it may be necessary to force marginal producers out of the market. The experience with aluminum, copper and tin in the years 1950-1970 does not support this theory. In 1950, the average prices in the United States market as reported by the American Bureau of Metal Statistics were 17.74 a pound for aluminum, 21.24 a pound for copper, and 95.54 a pound for tin. The corresponding figures in 1970 were 28.74 a pound for aluminum, 57.74 a pound for copper and 174.24 a pound for tin. Aluminum, with the greatest market growth, rose by 60%, whereas tin rose 82% and copper by 172%. Clearly, other factors were a more important influence on price than was the trend of demand To revert now to the capacity issue, during the period under review aluminum demand was rising so sharply that that industry had no sustained problem with surplus capacity. Instead, if anything, capacity may at times have been a constraint on demand. The industry succeeded in attaining explosive market growth through imaginative research and promotion programs. Some of this growth was the result of substitution of aluminum for other commodities – steel, copper, wood and glass as examples. But much of the growth was the consequence of developing entirely new products through technological innovation. Prior to World War 11, the number of aluminum producers was extremely limited. Alcoa and Alcan in North American and Pechiney and Alusuisse in Europe were the dominant firms. The developing countries had virtually no production and in Japan and Germany production was only a small fraction of the North American output. During the War years the United States had financed the construction of many new facilities. After the war these plants were sold by the government to Reynolds and Kaiser in order to foster more competition in the market. Subsequently many other concerns became aluminum producers, both in the United States and elsewhere and competition for markets intensified.

Jan 1, 1989

By K. Nielsen

The paper uses three examples to illustrate the challenges that the minerals industry is facing with regard to our image and the public?s perception of us. The paper then discusses communication with stakeholders as opposed to lecturing to the public and the authorities, and states that the industry needs to work more directly towards politicians and regulators as target groups. The conclusion is that we still have a way to go before the industry is doing enough to bring our message to the right people, but we are improving.

Jan 1, 2007

By K. S. Venkataraman

The physical properties of clay-water systems depend on the complicated system of forces between the clay particles themselves, and between the clay particles and the ions in the liquid phase. The kind and distribution of ions in, on, and between the clay particles and the size and the shape of the particles are the basic factors determining the macroscopic behavior of clay-water systems. Understanding the system requires a knowledge of the nature of the clay particles, their size, structure, composition, and surface properties, and of the manner in which they interact with ions [and molecules] in the surrounding liquid [or other medium]. The validity of Professor Brindley's words (Brindley, 1958), written three decades ago in the context of making pottery, whitewares, and electrical porcelains, transcends time, and the basic message is perhaps all the more important in the considerably expanded use of ceramics for structural, thermal, tribological, electronic, and other applications. Silicon carbide, silicon nitride, and sialons have been studied in the last two decades for high- temperature structural and tribological applications, particularly for using in internal combustion engines. Titanates, zirconates and niobates of barium, strontium and lead, have high dielectric constants, and are extensively used in the formulations for making capacitors. Hexagonal ferrites (molecular formula MO.6Fe2O3) are in use for making permanent magnets for fabricating miniature motors, and for assembling loud speakers, particle accelerators etc. Cubic ferrites such as magnesium-zinc ferrite and nickel-zinc ferrite are used as transformer cores, and for other high-frequency applications. In this context, Richerson's recent book (Richerson, 1984) on the general scope of traditional and technical ceramics is a good starting point for an overview of contemporary ceramics technology. Glasses are a whole class of amorphous materials used widely as sintering aids, and for making glass-bonded ceramics and glass-ceramic composites. Composites are yet another burgeoning field where two or more particulate components are used for improving the performance of ceramics. For all these applications, the inorganic starting materials are almost always submicron and near-micron powders. Understanding the powders' physicochemical properties, and their surface chemical interactions with the surrounding liquid/gaseous medium is-necessary for making reliable ceramic parts at competitive prices. Even though ceramics science and engineering has attained its separate identity in universities and the industry, ceramists themselves would concede that ceramics science is a cross-disciplinary field, having incorporated and assimilated within itself many principles from several apparently disjointed disciplines. Principles of material science, graduate-level physics and chemistry, polymer science, surface and colloid chemistry, transport phenomena, particle technology, unit operations commonly used in chemical engineering and mineral processing, and statistics and applied mathematics are integral part of any ceramics curriculum in universities. Added to this is the fact that all bench-scale successes in making ceramic parts are to be scaled-up for larger throughput operations. Understanding and applying process engineering principles of comminution, classification, drying, calcination, etc. then becomes essential. CERAMIC FORMING: Despite the diversity of the materials and processes, conceptually, the steps involved in making ceramic parts have remained the same over several decades: The different components for making the pan (usually one or more powders plus other forming and sintering additives) are proportioned and mixed thoroughly, and the well-mixed formulations are consolidated into desirable shapes known as "green bodies." Usually binders such as wax, clay, organic polymers and surfactants, whether dispersed or dissolved in a suitable liquid are used during mixing the batch for giving strength for the green bodies. In the dried green state, the inorganic powders typically occupy only 55 to 60% of the bulk volume of the body, depending on the particle size distributions of the powders and the forming history, with mostly inter- particle voids accounting for the rest of the void volume. SINTERING: The formed bodies are then fired in high- temperatures kilns/furnaces during which the parts are exposed to a predetermined temperature profile, and "soaked" for a certain duration at the final high temperatures, typically between 1200 K and 1900 K, and then cooled to room temperature. The gaseous atmosphere in the furnace is controlled (oxidizing, reducing, or inert) when necessary. During the initial stages of firing, volatile liquids evaporate, and during the intermediate temperatures between 400 and 600 K, the the organic polymeric additives pyrolize and oxidize into water vapor, CO, C02, and other gases. At still high temperature, the glasses, when present, soften, and simultaneously, the ceramic particles rearrange into a network of grains with definite grain boundaries so as to reduce the total interfacial free

Jan 1, 1990

By Paul Saxton

INTRODUCTION AND SUMMARY This short paper deals with the history of the Nickel Plate Mine from 1898 to 1987, with the major focus on the time period 1984 to 1987. Operations from 1898 to 1955 are reviewed in a cursory manner with the emphasis on some interesting points in the early 20th century. A review of the major exploration work carried out in 1984 to 1987 is presented and the process of moving the project through feasibility, government permitting and construction is described. The Hedley gold camp is situated approximately 40 kilometres east-southeast of Princeton, in southern British Columbia. The area has had a long history of gold mining and between 1902 and 1955 approximately 1.5 million ounces of gold were won from several mineralized skarn orebodies. Most production came from the Nickel Plate and Hedley Mascot mines. AN EARLY TO MID 20TH CENTURY SUMMARY The Nickel Plate is one of the oldest mines in the province. The mine had operated from 1904 to 1930 and, after a period of shutdown, from 1934 to 1955. The mine was revived in 1967 for exploration and. will resume production during the first half of 1987. In the first period the Yale Mining Company and Daly Reduction Company operated for six years and Hedley Gold Mining Company for twenty-one. In the second period the mine was operated by the Kelowna Exploration Company Limited and Kelowna Mines Hedley Limited for twenty-one years. In the present period the mine has been revived by Mascot Gold Mines Limited.

Jan 1, 1987

By D. Maxton

INTRODUCTION This paper traces the application of High Pressure Grinding Rolls (HPGR) at industrial and pilot scale in Australia. The Argyle Diamond Mine installed the first of two smooth segmented HPGRs during 1990 in an open-circuit secondary-tertiary crushing application to increase throughput. In 2002 a third HPGR was added to improve liberation and so increase the recovery of smaller diamonds. The latest improvements in wear technology (tyre with tungsten carbide studs) were incorporated in the design of this machine. Extensive HPGR pilot-plant trials were undertaken during the 1990s at both the Kalgoorlie Consolidate Gold Mine and the Boddington Gold Mine. The purpose of these trials was to evaluate HPGR as a method to increase throughput, as an alternative to SAG milling, and also to ascertain if downstream benefits existed. One of the challenges for HPGR circuit designers is to translate what occurs at small laboratory and pilot scale into what is likely to happen in a full-scale circuit. Scale-up from pilot machine results is normally recommended by manufacturers. However, such tests need relatively large quantities of material, particularly if meaningful data on wear are to be obtained. Laboratory tests are preferable, as they need relatively small quantities of ore, but may be questioned in terms of how they relate to full-scale operation. Modelling and simulation have played a particularly important role in this respect in Australia. Models are available which have proven to be very accurate at being able to scale throughput and specific energy response from laboratory to industrial machines. More recently, work in Australia has also been done in developing a model which has the potential to scale laboratory wear data as well.

Jan 1, 2004