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By P. J. Mackey, J. B. See, D. G. C. Robertson

The production of iron and steel and non-ferrous metals by pyrometallurgical processes will remain a critical element in meeting the demand for materials in both developed and developing nations. Given the important need to reduce and minimise greenhouse gas emissions the technological focus of future pyrometallurgical R&D by universities and industry alike must concentrate on sustainability issues such as improved energy efficiency, recycling and waste minimization. Continued efforts are also needed on process optimization and new process development with a view to reducing capital and operating costs of the new large “mega” plants. Using the academic and industrial backgrounds of the authors, the present paper reviews the current status of R&D in pyrometallurgy in university departments with a particular emphasis on sustainability issues. The role of industry and government laboratories is also reviewed although primarily for developed countries. The paper also includes comments and suggestions on the future requirements for education and R&D in pyrometallurgy in developed countries to maximise sustainability. It is also suggested that future R&D in pyrometallurgy will be even more concentrated in developing countries – most notably China.

Jan 1, 2014

By T. Karalis

Perlite is a generic term for naturally occurring siliceous rock. It is a form of natural volcanic glass the main constituent of which is amorphous silica (70-76%). Perlite, when heated rapidly to its softening temperature range, expands from four to twenty times its original volume, due to the presence of 2-6% ?combined? water, in a manner similar to popcorn as the H2O molecules vaporize and create countless tiny bubbles, which account for its exceptional physical properties: light weight (30-150 kg/m3), low thermal conductivity, cellular structure, in general. These properties make perlite adaptable for numerous end-uses, which can be distinguished into 2 categories: Expanded perlite applications in: a) Construction Materials market (e.g. Acoustical Tiles, light-weight insulating Mortars, self-levelling Concrete), b) Agriculture (e.g. Hydroponics), c) Food and Chemical industry (e.g. Filtration Media, Filler, etc.), d) Insulation and Heat resistance technology (e.g. Cryogenic vessels, Refractory Bricks, etc.). Unexpanded Graded perlite applications in: a) Phosphoric Fertilizers industry (additive in H3PO4 production), b) Foundry technology (slag-aid, insulating and heat resistance agent).

Jan 1, 2006

By Mark E. Emerson

Foreign and domestic companies find the mineral potential of this country's stern public lands, its capital markets, political stability, and "open-door" policy attractive for hard mineral exploration. Traditionally, exploration in the US has been geographically based and responsibility oriented at the district level. The 1970s brought a decentralized approach to exploration as major non-metal companies began to diversify into hard minerals. The emphasis was on capital intensive metal and energy projects involving bulk-tonnages. The recent economic downturn in metals has caused many of the new participants to withdraw from the mineral scene. The surviving companies have shifted their emphasis toward medium scale precious metal projects having high operating margins and rapid return on equity. Exploration expenditures in the United States are now principally focused on gold and silver to the exclusion of practically all other commodities. In the search for precious metals companies have scaled back their exploration efforts and have began to apply new approaches to target selection. The search is being assisted by rapidly evolving conceptual models. The change in orientation has led to numerous new discoveries. The finds are essentially "rediscoveries" that c,-re previously uneconomic. The majority are low-grade surface deposits that have involved low discovery costs and short lead times for development by low-cost mining and beneficiation methods. The emphasis on gold to the exclusion of all other commodities raises questions regarding the direction of exploration in the US for the rest of the 80s.

Jan 1, 1984

By T F. Guerin

Explorationn and mining have shown to cause significant impacts to the terrestrial and marine environment. Current mining and exploration techniques are outlined in the light of their potential to impact upon the environment, ie negligibly, negatively or positively. A profile of five Australian-based gold producers is presented. The development of protocols to specifically deal with the highly regulated and ever changing, mining and environmental legislation. demonstrates mining companies can successfully opcrationalise the concept of sustainable development.

Jan 1, 1992

By George C. Branner

BAUXITE is produced in Arkansas from two mining districts in the central portion of the State. These are (1) the Fourche Mountain district, immediately south and southeast of Little Rock in Pulaski County, and (2) the Bauxite (town) district, about five miles east of Becton in the eastern part of Saline County. These two mining districts are about twelve miles apart, separated by territory which, so far, has produced a negligible amount of commercial ore. Mining was by open-pit methods exclusively until 1924, when underground methods came into use. From 1924 to 1930 about 40 per cent of all of the ore produced in Arkansas was mined by underground methods, mainly by retreating caving.

Jan 1, 1935

By W. A. LaVenue, W. M. Houston

Pebble phosphate mines of Florida have been established from south of Hardee County to north of the Georgia state line, a distance of over 200 miles. Mining has been carried out on an ever-increasing scale since 1885, but phosphate deposits that can be mined on the economical standards of today, are confined in a roughly circular area about 30 miles in diameter, generally within Polk and Hillsborough Counties, in the central part of the State. The phosphate deposit, which is in the Bone Valley formation of Pliocene age, is covered by Pleistocene terrace deposits of unconsolidated quartz sand. The matrix is composed of approximately 1/3 clay slimes, 1/3 silica sand and 1/3 phosphate pebbles. The phosphate usually occurs as rounded pebbles, ranging in size from about 1 in. down to approximately 400 mesh. The phosphate may vary from well-defined hard pebbles to soft weathered rock. The color and character of the phosphate will range from smooth buff pebbles to black and white "salt-and- pepper rock." The screen size distribution varies considerably between locations; the recoverable phosphate may extend down to the 400-mesh size in some areas, while in others the phosphate may cut off sharply at about 35 mesh.

Jan 11, 1962

By Emerson J

Drilling has always been one of the most important parts of the exploration process with most companies spending around 25% of their budget on drilling. Although superficially there appears to be little difference in drills and drilling practice a number of major refinements have taken place over the last decade that have significantly changed the drilling scene. One of the most important advances has been in hydraulic engineering giving rise to the Dual Purpose top drive drilling rigs. These have led to significant productivity increases with the high rotation speeds and longer fleets. Downhole technology has also advanced with better hammers, stronger drill rods, impregnated coring bits and improved drilling fluids. Although geologists continue to measure drilling performance on a cost per metre basis, greater consideration is at last being paid to the quality of sample produced. This is particularly the case with RC drilling where quite sophisticated automatic and semi automatic splitting devices have been developed. Drill operators are now required to be experienced in both Diamond coring and air drilling and be better qualified to maintain the more sophisticated machinery. Management of drilling companies or drilling divisions has also had to change to accommodate both the high capital cost of equipment and the demands of keeping drilling a cost effective exercise.

Jan 1, 1987

By Ed Coulter

Nevada has a population of 1.2 million people of which only 21% or 312,rIXl are native born Nevadans. he population between 1980-1990 grew a record of 389%. and ls the fastest growing state in the union. While only 2.5% of the total population are direct employees of the mining industry, excluding Reno and Las Vegas, one out of every three people living in Nevada work for a mining related industry.

Jan 1, 1991

By Harry Perry

The Bureau of Mines is glad to have this opportunity to discuss its present Coal Research Program and its significance to the industry with a group which has for many years been representative of the coal producing community. We believe we have a dynamic program that will help our vast coal resources to find their proper place in the U. S, economy. The present coal research activities of the Bureau are conducted in three organizational subdivisions: Minerals Research, Mineral Resource Development, and Health and Safety. All investigations are carried out in Bureau research facilities located in different sections of the country, Since its creation by the Organic Act of 1910 and subsequent amendments, the Bureau has worked closely with the coal industry--first by providing assistance in mine safety for anthracite and bituminous coal mining, and since that time, in providing information on conservation, safety, mining, preparation, and utilization.

Jan 1, 1966

By V. Tang

In this paper, Chinese economic situation are estimated and prospective developments predicted to assist those US firms who have been trying to do business in China, or are considering to pursue the China market.

Jan 1, 2010

By B. D. H. Knights, M. A. W. Bryson

Flotation of PGM ores, specifically UG-2, presents a number of technical challenges. These centre on the prevalence of chromite. Subject to over-grinding, chromite is primarily recovered to the flotation product through entrainment. This is of unique concern as it must be kept below a threshold for downstream smelting, with significant operational and monetary penalties being imposed should it exceed this concentration. A number of strategies have been developed to maximise PGM recovery in the presence of this unwanted contaminant. Specialised flowsheets form a vital basis and advanced control algorithms further enhance PGM recovery while minimising the recovery of chromite. Advances in Mineral Processing Science and Technology Proceedings of the 48th Annual Conference of Metallurgists of CIM Sudbury, Ontario, Canada Edited by

Jan 1, 2009

By R. W. Carn, D. Vincent

Environmental Considerations With significant increases in bulk coal movements through terminals, operators are under constant social and political pressure to reduce or remove environmental pollution problems incidental to their operations. To meet these requirements, both equipment manufacturers and terminal designers are endeavoring to design equipment and systems with stringent environmental controls. The most challenging environmental problems facing coal terminal designers and developers are terminal siting restrictions, dust control, and noise abatement. Terminal Siting Finding a suitable site can be a difficult problem because of public concern over coal dust or the impact of a terminal on the surrounding community or natural habitat of the area. Often the only suitable flat land available for terminal development is on a tidal estuary or salt water marsh with great environmental value. In many cases a period of four to six years of full environmental and social assessment has been needed. A recent example of such difficulties is the expansion at Roberts Bank, British Columbia, where environmental impact assessment studies and their public review took almost six years from initial expansion applications until the time of approval. Dust Control Modern coal terminal dust control techniques usually consist of water sprays at strategic locations to suppress dust. The application points include rail car or barge dumper, main conveyor transfers, perimeter sprays around stockpiles, stacker/reclaimer, ship-loader transfers, and loading spout. The water sprays may include a chemical wetting agent or surfactant to reduce the water requirement and increase effectiveness. Recently there have been advances with development of effective micro foam agglomerating agents. In these systems, a micro foam with very small bubble sizes is sprayed into the coal stream. The foam fills the interstices between coal particles and wets the coal fines. These systems have proven to be very effective and usually one application before stockpiling and one upon reclaiming will markedly reduce the coal dusting. Stockpile perimeter sprays can be operated either manually or at the sophisticated terminal, actuated by a computerized control system that senses key environmental conditions such as humidity, precipitation, and wind velocity. Most modern terminals collect the drainage from the stockpile area, remove the solids in settling basins, then recirculate the water to reduce water requirements and effluents from the site. Dusting of long-term storage stockpiles can be reduced by spraying the piles with chemical resin or latex binding compounds to seal the surface. These compounds also can minimize erosion of the pile by rainfall. Dust collection with air evacuation systems and cyclone or wet scrubbers can be used at key areas such as rail car dumpers, main conveyor transfers, and ship-loader spouts. The trend in dust control is away from dust collection since most dust collectors are high maintenance items requiring good operator supervision and servicing. Coal handling conveyors are usually open and uncovered. However, in areas requiring special attention they may be covered or even completely enclosed. Dust generation from terminal roads is often a significant amount of the total dust emitted from a terminal. To reduce this dusting, roadways where traffic is heavy can be paved or sprayed by water trucks. Speed limits can be enforced and use of tracked mobile equipment for stockpile handling rather than rubber-tired loaders is encouraged by authorities. Noise Abatement Terminals located close to residential areas are often faced with noise control problems. Noise can be one of the most difficult environmental problems to solve. Usually, use of electrically-powered equipment is encouraged to reduce noise levels. Rail car dumper houses can be totally enclosed to reduce both dust and noise emissions. Diesel locomotives can be fitted with special muffling devices. Green belts of trees surrounding a terminal or the ap-

Jan 7, 1983

By Robert W. Carn

This paper presents the concepts which are presently being utilized in the design of coal export terminals. Criteria for selecting a viable site and establishing the terminal plan are presented. Factors affecting the design of the terminal as well as the present techniques and procedures in use today to determine the optimum use of equipment will be discussed along with the current trends in export terminal control systems. Finally capital and operating costs for a typical export terminal are reviewed.

Jan 1, 1982

By R. W. Carn, D. Vincent

During the next 15 years, US coal production is expected to double, with the increased production evenly divided between the East and the West. Along with greater production, coal export markets should increase dramatically from East, West, and Gulf Coast ports. The annual overseas export capacity of US coal-loading terminals is expected to rise from 147.1 Mt (162.1 million st) in 1981 to a minimum of 278.1 Mt (306.6 million st) in 1985, according to the US Maritime Administration. Increased coal production and use will lead to more development of import and export terminals, a vital link in the coal transportation chain. With continually escalating capital costs and the competitive markets that the terminals will serve, a well designed and efficient terminal is necessary. This article begins a two-part series that presents concepts presently used in coal export terminal design. Part I looks at site selection factors and equipment needs, while Part II will examine environmental considerations in building a terminal as well as typical capital and operating costs. The world is nearing the end of the oil era. In a few years oil will not be available to sustain the growth rate and increasing standard of living we have known in our lifetime. The big question is what energy era are we moving into? With the decline of readily available oil reserves and rapidly increasing prices, many countries are trying to switch to alternate energy forms. While intensive efforts to find new oil reserves continue, alternate energy sources such as natural gas, coal, synthetic fuels, nuclear, hydroelectric, solar, and wind power are being developed. Recent indications are that coal is expected to bridge the energy gap over the next 25-30 years until the technology and economics of the alternate energy forms reach satisfactory levels. Use of coal for energy is receiving strong attention due to its long-term availability (200-300 years minimum), relative ease of development, and its low cost per unit of power produced. By the year 2000, it is expected that 25% of world energy supply will be met by direct coal combustion and possibly another 5-10% by synthetic fuel from coal. Coal's expanding share in the world energy market, along with an increase in coking coal requirements, will result in a large increase in the world's seaborne coal trade. Recent statistics and projections for the future are shown in Table 1. This phenomenal development rate includes increases in both coking and thermal coal requirements. Because of the rapid increase of seaborne coal trade during the last 10 years and the even greater projected increase of trade to 2000, various sectors of the coal industry are faced with enormous technical challenges and huge investments in equipment, land, transportation systems, and port facilities. Very large bulk terminals are under development throughout the world. Latest surveys indicate that there are about 30 new coal export and import terminals under consideration and at least 30 existing terminals have expansion programs planned or underway. With the high cost of borrowed capital and rapid inflation rates there is great emphasis on new planning and design techniques to minimize capital and operating costs of coal transportation systems. Terminals A total coal supply system can be considered to consist of one or more mines; a train, barge, truck, or other haulage system; an export terminal; a fleet of bulk carriers; a receiving terminal; and possibly, local inland distribution networks that include barges and railways. Terminals, though only a small link in the total transportation system, play a key role in overall system efficiency. At ports or inland distribution centers, terminals act as transportation links bringing trains, ships, barges, or trucks together for cargo transfer and temporary storage. A well-designed terminal can provide maximum independence between two modes of transportation and optimum freedom for intermodal interference. A terminal acts as a buffer between the two transportation modes by providing sufficient storage capacity so a ship need not wait for its cargo on, for example, a train-by-train basis, but can load immediately from the ready stock. Similarly, a train need not wait for a ship to unload its contents but can dump immediately into storage. A terminal also can be used to properly mix various types of coal to satisfy a buyer's requirements. Consider the relative value of various production and transport segments for a typical steam coal

Jan 6, 1983

Is your company paying taxation on profits which are partly illusory?ò Are unions making wage demands based on erroneous notions of the real level of value added to your companyÆs production?ò Do you receive historic data on profit contributions by different products, or for different market areas, which you feel may be misstated?ò Do you find that cash is not always readily available to pay dividends out of reported earnings because, it is required to finance additional working capital without a real increase in the level of activity?ò Are your planning and budgeting routines hampered by the need to rely on historic financial data which bear little resemblance to what the future may hold for your company?ò Are you able to maintain your business at its optimum operating capability or do you feel each year that it becomes more and more difficult to achieve the same volumes of prdduction at the same level of return on assets employed without having to raise more capital?If your answer to any of these questions is "yes", then it is very likely that Current Cost Accounting (CCA) has something to offer you!characteristics of the mining industry and for single venture mining operations.

Jan 1, 1984

By K. D. Hester

This paper will review the metallurgical aspects of the completed expansion program at Quirke, and the current rehabilitation and refurbishing program at Panel. During the Quirke program, completed at the end of 1977, the plant capacity was increased from a nominal 4,500 to 7,000 short tons per milling day. The expansion of crushing, grinding, neutral thickening and filtering, leaching, partial neutralization, sand-slime separation, sand washing, C.C.D., clarification, ion exchange, mine water treatment, and tailings neutralization and pumping will be considered. The application of Enviro-Clear thickeners in the mine water treatment circuit and in the C.C.D. will be briefly reviewed. An automatic grinding and classification circuit for limestone will also be covered. The refurbishing program underway at Panel will be discussed. The Quirke and Panel plants will be contrasted and compared. In particular, reference will be made to environmental considerations. The innovative system for producing yellow cake at Panel, LAMIX, will be considered as well as the proposed treatment system for Panel tailings.

Jan 1, 1979

By W. L. Price

Recent publication of United States Bureau of Mines figures showed that the sand and gravel (3) industry is the largest single mining industry in the United States in term of yearly tonnage produced. The yearly production of over 500,000,000 tons per year now exceed bituminous coal production. This disclosure caught unawares many observers who have not been following closely the rapid-growth of this phase of mining. Along with this steady growth in production, the sand and gravel industry has gone through an accelerated and varied program of beneficiation in a period of the last ten years.

Jan 1, 1958

By Douglas A. Grieg

THE EXCUSE for producing still another paper dealing with the oilfields of the Middle East is the overwhelming importance of this area to everyone, both inside and out of the oil industry. Figure 1 shows the area defined as the Middle East for the purpose of this paper. No description of what constitutes the Middle East is generally acceptable to everyone and, in fact, in many parts of the world it is referred to as "Western Asia". At the time ?the writer went to work as a geologist in the Middle East -this was in 1926 -there were just three known oilfields, namely, Hurghada in Egypt, Naft Khaneh in the Transferred Territories of Iraq, and Masjid-i-Sulai-man in Persia. Their combined producing rate at that time was around 100,000 barrels per day. Toda y, just thirty years later, some forty-two fields have been proven to exist, and a recent discovery in Syria -if commercial -may add one more to the list. Producing rates at the end of last year ( 1956) were approaching four million barrels per day. This sizable figure re presents nearly 23 per cent of the total Free World's production. What is more important still, something over 70 per cent of the Free World's proven oil reserves are known to exist in the subsoil of the Middle East.

Jan 1, 1957

By A. Wieniewski

The observed progress in technology of non-ferrous ores enrichment and condition of machines and equipment in the ores concentrators on the one hand have brought a possibility and on the other resulted in necessity for introduction of modernization actions. Positive results of investigations into influence of chemical modification of selected products of enrichment process on copper ores enrichment results gave possibility for implementation of chemical-flotation technologies of ores enrichment. The substantial development in flotation machines structure has contributed to modernization of flotation process resulting in increase of enrichment efficiency. The paper presents the idea and results of chemical modification of difficult in enrichment semi-products in the technology of copper ores enrichment and the results obtained after application of the modernised technology. The structure of large-volume flotation machines used in various stages of flotation and current situation in modernization of flotation process in copper ores concentrators are also described. The paper presents industrial-scale results of flotation after application of modified flotation reagents of collector group. Introduction of modifiers into the widely used xanthates resulted in increase of copper recovery in concentrate.

Jan 1, 2014

By D. Stone, N. J. Aslin, W. Webb

In today's modem copper electro-refineries, increasingly higher average current densities are being employed. With these increases many refineries are approaching their limiting current density. The nearness of the average operating current density to the limiting current density has placed increasing emphasis on the need to maintain an even current distribution. This paper explores the importance of maintaining even current density and discusses the factors, processes and practices that are necessary to achieve and maintain high quality production at high operational intensity.

Jan 1, 2005