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By John T. Day, Lex L. Udy, Mark L. Thomas

When we consider that the purpose of blasting is to fragment rock or ore so it can be subsequently handled and processed, we can see that the cost of blasting, in reality, affects all downstream steps of the mining (and in some cases) production processes. The productivity of all subsequent operations is influenced by the degree of fragmentation of the primary blast.

Jan 1, 1987

By Lawson F

A rotating disc geometry has been used to provide a uniformly accessible surface for a kinetic study of the cementation of the metals cadmium, lead and silver from dilute aqueous solutions. This work is an extension of studies carried out on the Cu/Zn and Cu/Fe systems for which the rection rate was found to be completely solution-phase mass-transfer controlled. When the amount of material deposited was greater than 0.2 to 0.4 mg/cm2 there was an apparent enhancement in e which is attributed to the formation of a roughened deposit. This same phenomeon was obseived in the Cu/Zn Cu/Fe systems. Again, the rate of reaction of each system investigated was found to be solution-phase mass ,..~sfer controlled.

Jan 1, 1970

By T. Egleston

The materials containing copper which are refined in the United Statrs, are, for the most part, the natiye noppers of Lake Superior. IJntil quite recently but little pig copper Was made for sale, and that came principally from the pure sulphorous ores of New England and the Sonth, and was generally sdd to reSneries not far from the ore filrnaceu. A stnall aiuoiint found its way into the'niarket which was produced either as the by-product of the treatment of gold and silver ores, or as the result of the treatment of impure copper ores; but both these grades, on account of the impurities they contained, were loolced on with stlspicion, and were not sought for. A11 the grtlGis of pig coppcr are sold by the unit of oopper contents, a great redtiction being made in the price when impurities are present. There are at the present time only three works which treat native copper, the two of the Detroit and Lake Superior copper Company, and the works of C:G. Hussey & Co., in Pittsburgh. There are a few works ivhich smelt sulphuroris ores and refine their pig; bo sides these t1le1-e arc a few siuall works where gig copper is refined uuly. Some of these purcIlase blscir copper, refine scrap, or simply refine such grades of ingot copper as are found in the market, but nlostly that from Lake Superior, for the purpose of getting it into swh shapes that can be handled cpmtriercially to advantage, such as in making large plates or high grades of wire fir electrical purposes. A nomher of such works are situated in the Xaugaturk Vatley aud elsewhcre in New England. The recent discoveryof vnlt~sblc ores in Ariarona makm it probable that within a few year8 the refining of capper In the United States will make great develupments. Up to the time of the discovery of the mines on Lake Superior, only a very small quantity of native copper had ever been foond, not sufficient to justify the erection of worlrs fbr its special treatment. It had, besides, never been found in very large maweq so that the discovery of greabblocks of it presented serious difficulties, not oolp in mining it,-I- but in bringing it into a merchantable condit'ion. It seemed a very simple process to melt these large maws,

Jan 1, 1881

T. M. Morris (Measurement and Evaluation of the Rate of Flotation as a Function of Particle Size, P. 794), was the commanding officer of a patrol craft charged with guarding Aleutian waters against infiltration by the Japanese during World War II. Before going into service, he was an assistant research engineer with Anaconda Copper at Anaconda, Mont., and later a metallurgist with Tennessee Copper Co. Presently he is a professor in the Department of Metallurgy, Missouri School of Mines, Rolla, Mo. A member of the AIME, he is a graduate of Columbia University and the University of Missouri, with a Bachelor of Science, Master of Science and a Ph.D. Professor Morris is the author of a previous paper for the AIME, Measurement of the Equilibrium Forces Between an Air Bubble and an Attached Solid in Water. An outdoor man by predilection, he enjoys bird watching and hiking in his free time.

Jan 1, 1952

The refractory industry in New Zealand is small, consisting of two main manufacturers - one at Huntly and the other at Kamo. Together these would have an annual refractory production of about 30 000 tonnes. The industries which use refractories include two steelworks, NewZealand Steel Limited and Pacific Steel Limited, the former is involved in continuous casting from sponge, iron and scrap steel and the latter is involved in ingot teaming from scrap steel and steel billets; One aluminium smelter, cement works, dairy companies, small foundries producing engineering requirements and many other small users. The New Zealand manufacturers produce refractories in thefire brick range, that is up to 50 per cent alumina content (ignited basis), based on indigenous raw materials and in the high alumina range up to 85 per cent alumina content (ignited basis) based on imported bauxites. All of the basic refractories high purity silica and high alumina low alkali refractories and many of the higher grade acid resisting refractories are imported.

Jan 1, 1976

The Permo-Triassic Bowen Basin developed during the final stages of the Tasman Orogenic Phase in eastern Australia. The basin has considerable economic value as a source of coal, natural gas and precious metals. The basin, which is of controversial origin, is preserved as a north-south trending, asymmetrical syncline bounded in places by faults. It is here interpreted as a retroarc foreland basin which developed on the landward (west) side of a continental arc associated with continent-ocean plate convergence. Initiation of the basin occurred via back-arc extension in Early Permian times, coincident with a phase of talc-alkaline arc volcanism. Early Permian, mostly marine sedimentation gave away to extensive coastal and alluvial plain depositional systems in Late Permian times, coincident with a resurgence of arc volcanism. Triassic sedimentation was almost entirely alluvial and coeval with westward propagation of thrust sheets from the eastern basin margin. Compressive tectonics climaxed in Middle to Late Triassic times, terminating sediment accumulation and uplifting the entire area.

Jan 1, 1990

By M. A. Barclay, D. Samson, A. M. Esteves

Several companies have adopted policies and standards aimed explicitly at increasing ‘local procurement’, recognising that local economic participation has benefits for companies and communities alike. From a corporate perspective, local economic participation is seen as one means of maintaining a social license to operate, as well as ensuring reliability of supply by having a supplier located nearby. From a community perspective, the participation of local businesses in the resource project is a means by which the benefits of resource development can flow into their communities. This paper is based on the research undertaken to produce a good practice guide for the mining, oil and gas sector. Our research revealed that the extent to which the local community will actually benefit from local procurement initiatives is dependent on the capacity of the community to supply goods and services to the project and, even more importantly, on its ability to adapt to the inevitable changes that accompany large-scale resource development. We provide guidance on adapting impact assessment tools to guide planning of procurement interventions.

Jan 1, 2011

By B. W. Cavender

Capital investments are made for a variety of reasons, ranging from providing incremental capacity at existing operations to developing and implementing new technologies intended to radically improve a company's capabilities. These projects generate very different business opportunities and create value in distinctive ways. For incremental improvements, the capital budgeting process assures at least a loose fit between short-term goals and readily available resources. However, the criteria used to evaluate capital projects often prevent a company from committing to more aggressive goals, which lie beyond the firm's current abilities or resources. Such projects may not have clearly identifiable future cash flows, and the degree of interaction with other projects and the nature of the risk incurred may be difficult to estimate. Additionally, by focusing only on quantifiable benefits, the budgeting process often fails to recognize "soft" improvements such as increased operating flexibility or new knowledge generated by such projects. By rejecting these projects, the capital budgeting process may actually harm the company's future competitive position.

Jan 1, 1999

By Eric Konigsmann, Doug Spence, Scott Jones

"The Williams Gold Mine is located in the Hemlo camp of Northwestern Ontario and is one of Canada’s largest gold producers with annual gold production of 400,000 ounces. The operation is owned and operated as a 50:50 joint venture between Teck Cominco Limited and Barrick Gold Corporation.In July 2002, the decision was made to introduce paste backfill produced from mill tailings as the primary backfilling method in the mine and to decommission the existing cemented rock fill system. This required a fast track design to be completed for both a surface paste backfill plant and an underground paste distribution system followed by an intensive construction phase through the fall and winter of 2002/2003. The paste system was commissioned on schedule in late April 2003 and was in full production within 4 weeks of the initial start up. Overall, the project duration was only 42 weeks from initial project release to commissioning and it was completed $2 million under the budget of $14 million.This paper presents an overview of the lab testwork and process flowsheet design, process control methodology and describes the construction and commissioning phases of the project. Preliminary paste plant performance and operating cost data is also presented.IntroductionThe Williams Gold Mine is located in Northwestern Ontario adjacent to the Trans Canada Highway in the Hemlo Gold Camp as shown in figure 1. The mine currently produces approximately 400,000 ounces of gold annually and is owned and operated as a 50:50 joint venture between Teck Cominco and Barrick.The deposit was discovered as part of the Hemlo gold discovery in 1981 which led to the development of three mining operations within a 2 kilometre radius. The neighboring operations are the Golden Giant Mine, currently owned and operated by Newmont Gold, and the David Bell Mine, currently owned and operated by the same joint venture which is running Williams. David Bell ore is blended and milled in the Williams concentrator."

Jan 1, 2004

By Steve Dillingham

With the millennium fever all but faded, we look to a new century filled with awe and excitement. We step forward in time, marveling over the achievements of the 20th century and wondering what the next 100 years could possibly bring. Will there ever be another time that produces such technological advances, economic progress or social changes? Keeping pace with the awesome accomplishments of the past century has not been an easy task and we must prepare ourselves for the possibilities of the future. Take, blasting safety for instance. We all know that safety is personal - a culture - promulgated not only by the company by which you are employed, but, by a sense of your own personal responsibility that must constantly be reinforced through awareness, training, and discipline. Great strides have been made in blasting safety since its crude beginnings, however, safety consciousness becomes even more important as technological advances and scientific progress are made in the coming years. It all begins with a positive safety attitude where every employee habitually examines each situation encountered, identifies potential hazards, and takes precautions to avoid those hazards.

Jan 1, 2002

By K. Noda

Tamano Smelter of Hibi Kyodo Smelting Co., Ltd. is carrying out a low cost production using a Tamano Type Flash Smelting Furnace (T-FSF), which is an improved version of Outokumpu Type Flash Smelting Furnace but without slag cleaning furnace and also by developing its own coke combustion technology. Coke combustion technology that is the basis of the system has been improved several times and, at present, it has evolved to a stage where it can be reproduced on the Computer guided system for Coke Combustion in the T-FSF (CCCT) using a general- purpose computer. This CCCT is featured by 'its trend control and predicting function, and an operator can freely control the operation parameters so as to control the operation flexibly. We have recently developed an overall energy reduction system covering the Smelting Plant to Sulfuric Acid Plant, which we call an Optimum Low Cost Operation System (OLCO) to reconsider the energy costs including coke, heavy fuel oil, and electric power. In this report, we would like to present the recent operation of T-FSF based on CCCT as well as the optimum energy operation utilizing OLCO system.

Jan 1, 2002

By J E. Eberhardt

Ore sorting has long been used to raise the efficiency and thus lower the environmental impact of mineral processing operations. It was first instituted as hand sorting, according to a humanly perceived difference in the ore, but is now automated using large mechanical sorters in order to meet the high tonnage throughput required in most minerals processing applications. In the past, ore sorting was generally used as a niche processing route when other approaches failed, and in this context, consequential environmental benefits are often not the first consideration in adopting sorting. When applicable, ore sorting offers environmental benefits in reductions in fines waste, reagent usage and energy consumption in milling. Although there are significant opportunities for the use of ore sorting technology in many minerals processing operations, industry applications, to date, have been limited mainly to the processing of diamonds, magnesite, talc and uranium ores. This limitation has principally been due to a lack of suitable sensing technologies for a wide range of ore types. The authors report on a wide-ranging review of the automated sorting of mineral ores, and in particular, on methods for discrimination of ore characteristics prior to mechanical sorting.

Jan 1, 2002

By P. M. Solozhenkin, V. P. Nebera, V. D. Skorohodov

"Aqueous dispersions of air specifically prepared on the basis of flotation reagent solution acquire active properties in relation to the solid surface and may be imply as a medium for flotation ores. Such aerated solutions were defined as Activated Aqueous Dispersions of Air (AADA) with 5-6:1 ratio and the procedure of mineral separation was defined as a flotation process under non-equilibrium conditions. These procedures differ from conventional flotation mainly in reagent interaction with minerals through their adsorption films on gas bubbles simultaneously forming flotation complexes. Gas-liquid mixture is kept till an adsorption layer of reagents close to the limit value is formed on the surface of bubbles. The theoretical basis of AADA is considered.The results of two-phase gas- liquid mixture (AADA) were studied. Two versions of AADA were considered. Electrical surface potential of the air bubbles with the surfactant film, untreated minerals particles in Coulomb attraction and flotation complex formation were analyzed. Special flotation machines were constructed for separation of mineral suspension in air dispersion, whose effectiveness was confirmed in flotation of apatite waste of Kovdor ore. FK-9 machine introduced on Kovdor iron ore combine for the recovery of apatite from current departures of factory. The froth product contained 7.2 % P2O5, with recovery of 44 % apatite, which was processed for getting melted phosphoric-magnesium fertilizers."

Jan 1, 2003

By Howard C. Turnage, Dana T. Updyke

An evaluation was made of one of several improved underground communication systems sponsored by the U.S. Bureau of Mines. The system evaluated was installed in a typical metal/non-metal room and pillar mine and utilized UHF repeaters connected to a unique distributed antenna and passive reflector system which provided mine-wide communications. A microprocessor controlled data collection system was assembled and installed for the evaluation. Data consisting principally of times and durations of messages and identities of the originating transceivers was collected between February and August of 1982 (6 mos.). Analysis of the data shows that the principal benefits are reduction in time required for unscheduled maintenance and repair, enhancement of safety, and better coordination of production activities. A cost benefit analysis shows a net benefit over cost, although it is also concluded that the capacity of the system is greater than can be justified by current activity in the mine.

Jan 2, 1983

By Charles W. Rountree

Industrial Engineering in the industrial world is a relatively new field, having been conceived about the turn' of the century by Frederick W. Taylor, who was not satisfied with the hit-or-miss methods of evaluation and estimation. Through crude Industrial Engineering techniques never before used, he completely changed the bricklaying industry so that work accomplished was more than doubled. To help us better understand what we mean by Industrial Engineering, I think a very simple definition Is in order. Industrial Engineering is a scientific approach to problems in cost, production and operations: and is designed to provide a means of increasing producitivity and reducing costs through standards measurement and standardization of the best methods, practices and equipment, There are many complicated definitions, but pure and simply, it all boils down to providing the means for increasing productivity and reducing the cost. Industrial Engineering has been applied in manufacturing since Frederick W. Taylor?s time and in the last 20 years has grown in stature by leaps and bounds. It is a basic function of successful manufacturing companies and is an accepted fool firmly entrenched in manufacturing organizations. You may know of some successful manufacturing companies that do not employ Industrial Engineers as such, but someone in that organization is doing Industrial Engineering work. They have standards and controls whether they call it Industrial Engineering or not. The manufacturing industry has benefited from this tool; other wise, it would have been discontinued long ago.

Jan 1, 1958

By Richard B. Greenwalt

INTRODUCTION Direct reduction of iron ores has unquestionably become established as an important step in the worldwide steelmaking industry. The history of this development has been long and fraught with difficulty. In 1800, Champlain suggested the direct reduction concept using carbon and a shallow hearth vessel. Roughly 100 years later, Jones attempted a commercial process using carbon and producer gas in a rotary kiln. During the early years of this century, numerous attempts were made to start commercial direct reduction plants using such processes as Hoganas, Wiberg, Krupp-Renn, and others. Most of these were short lived, being abandoned due to a variety of technical and economical factors. Today, however, a new generation of direct reduction processes has emerged. We enter 1977 with at least 40 commercial plants in operation using 15 processes in 14 countries. These plants have combined total annual capacity of roughly 10 million tonnes of direct reduced product. Many articles have been written, and projections made, concerning the future growth potential for direct reduction. As is al- ways the case with projections, the numbers vary, but the outlook does not. Anyone who participated in the years of effort that have gone into this field of endeavor should be excited and justly rewarded by noting the shape of the curve in Figure 1.

Jan 1, 1977

By R. S. Dean

The possibility of cheap electric power for a number of mining areas in this country has suggested to many the idea of electric smelting of nonferrous ores in small units at or near the mines. The electric smelting of nonferrous ores was tested fairly thoroughly 20 years ago by United States Bureau of Mines and by others, and the fact that it did not achieve continuing workable success in any instance is sufficient proof that it offered no advantages at that time.

Jan 1, 1937

By McGuckin P. H, Logan A. S

The BHP Minerals' Cannington silver-lead-zinc deposit is located approximately 190 km south-east of Mount Isa. The deposit, is hosted by Proterozoic rocks beneath a thin cover of younger sediments, and contains a total estimated resource of 45.3 million tonnes at 11.1 per cent lead, 4.4 per cent zinc and 500 g/t silver. The deposit is separated by faulting to form a shallow, lower grade Northern Zone and a deeper, higher grade Southern Zone (Roche, 1994). Contract development of an exploration decline to test mineralisation in the Southern Zone commenced with the excavation of a boxcut in August 1993. The complex variably deformed Proterozoic sequence interpreted from drill core and intersected in the exploration decline has required a high level of practical rock mechanics input to achieve: ò appropriate support designs, ò a high quality of installation, and ò required development advance schedules. The Norwegian Tunnelling Index (Q System) in conjunction with regular face mapping is used as an operating tool to assist in decision making for ground support. Line mapping, discontinuity analysis and wedge assessments are conducted routinely to optimise ground support requirements in the decline, intersections and all other underground excavations. Throughout the project, an emphasis has been placed on developing a strong working relationship with the contractor to achieve quality assurance program targets.

Jan 1, 1995

By H. Rush Spedden

R. T. Hukki has extended his study of ball mill grinding at supercritical speeds with an excellent mathematical analysis of tumbling mill grinding. When he speaks of supercritical speeds he is referring to the original Fahrenwald critical-speed formula. He said that, as an example of the use of supercritical speeds, if a fine grinding mill of any type is wet-grinding ore of 3.5 sp gr with steel balls at a certain conventional subcritical speed, the same power input and capacity should be obtainable with autogenous medium of 3.5 sp gr at a speed 100 to 120 pct of the critical in a grate- type mill of the same effective size. In addition, he introduced what he calls the base mill concept which, he stated, makes it possible to compare performances of mills of different sizes grinding with a metallic medium or with an autogenous medium of any specific gravity and at any speed. He showed the use of this concept and explained how it makes possible the evaluation of mill sizes and motors for any grinding purpose at any accuracy well within the conventional standards of design in milling practice. He further stated that the maximum capacity in pilot plant mills with various media, either metallic or autogenous, has always been found to be within the supercritical speed range. In his discussion of this paper he substantiated these findings with statements showing the increased capacity obtained in a milling plant in Finland which followed his principles.

Jan 7, 1960

By Charles H. Behre

This paper discusses education and training for economic geologists other than petroleum geologists. Candidates enter economic geology through liberal arts colleges, engineering schools and university graduate study. Whatever their backgrounds, rigorous courses are desirable-now conceded in theory, but not adequately recognized in practice. Besides basic sciences (each studied long enough to give a fair comprehension of its basic tenets), a functional command of English and two modern foreign languages is needed, as well as a broad understanding of mining, milling and metallurgy. A year of economics and finance is recommended. Surveying and drafting are essential skills. Yet geology should be represented in each term; otherwise the initial enthusiasm for the science, once contact is broken, may never be regained. A five-year curriculum is thus designed to take care of all major requirements and culminate in the M. S. degree. This curriculum reduces "cultural" courses below the average liberal arts requirements, but this is regarded as necessary. The pursuit of "culture" is assigned, as in most engineering and medical curricula, to extra college years or extracurricular time. To avoid the danger of over-crowding the schooling, the Doctorate in geology is preferred wherever possible. Its two added years should permit wider professional education; more browsing in "cultural" pastures; due attention to broader social implications; and some training in the research now increasingly required of the mineral industry. "In-course" training through cooperation between school and industry is especially advocated. The Institute should take the initiative in stimulating this practice.

Jan 1, 1947