Competitiveness of the U.S. Minerals and Metals Industry (1990) / Chapter Skim
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3. Role of Science and Technology in Minerals and Metals Competitveness Issues
3. Role of Science and Technology in Minerals and Metals Competitveness Issues
Pages 56-78
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From page 56... ...
Revolutionary research transforms a system. The advent of in situ extraction 56
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From page 57... ...
Coal and the industrial minerals are also included, since the technologies serving them may also have applications to the minerals and metals considered in this report. The chapter is divided into the four components of the mining industry: exploration, mining, minerals processing, and metals extraction.
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From page 58... ...
Certain materials have been in great demand during specific periods, as with the uranium "rush" of the 1950s and early 1970s and the porphyry copper boom of the 1960s. Although precious metals currently command the majority of exploration budgets, there is increasing activity in copper (particularly oxide copper)
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From page 59... ...
The various computer-aided drafting programs can readily produce maps and sections at any scale required and can be color coded as desired. Geophysics Geophysical activities and surveys have not advanced as rapidly in the past 10 years as previously Magnetics, electromagnetics, induced polarization, and, to a lesser degree, gravity and seismic probes are still widely used, both ground based and airborne.
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From page 60... ...
Probes now available include acoustic velocity, natural gamma, self-potential, resistivity, caliper, fluid resistivity and highresolution temperature, bore-hole azimuth and inclination, dip meter, gammagamma density, neutron, induced polarization, and spectral gamma. These sensors can be used alone or in various combinations.
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From page 61... ...
minerals and metals industry by allowing the discovery of new viable deposits. Evolutionary improvements in exploratory technologies include · spatial and spectral image resolution to penetrate foliage and surface cover; · digital geophysical coverage of the United States magnetically, gray tationally~ radiometrically, and spectrally to a scale of one-half mile; ~ .
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From page 62... ...
MINING TECHNOLOGIES Current Mining Technologies Mining technologies are those required to expose and remove ores and minerals from their natural deposits. The development of current mining technologies reflects the following factors: · Cost of labor (both wages and benefits)
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From page 63... ...
Longwall technology, which is regarded by many as the most effective underground coal mining method and which will form most of the basis of future development, was imported from Europe. Limitations of Present Mining Technology Virtually every mechanized mining system used today was in use by the late 1950s.
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From page 64... ...
, and (~) obtain in situ measurements of grade variations, would improve the likelihood of discovering new deposits and contribute to the design of more effective mining equipment.
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From page 65... ...
· In situ mining is a potentially revolutionary mining method that could greatly improve mining economies and allow a human-free working environment, exploitation of low-grade mineral resources, and retention of waste underground. 1 MINERAL PROCESSING TECHNOLOGIES Current Mineral Processing Technologies Mineral processing has a critical role in determining the yield and quality of concentrates for smelting or other product preparation steps.
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From page 66... ...
by Blake (1858~; first use (1861~; introduced to Europe (before 1866~. Gyratory First competitive trial versus jaw crusher by Gates (1883~.
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From page 67... ...
RO[E OF S~CE 4~ ~~F I ! Early lest Notation cells Montana, circa 1915.
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From page 68... ...
Except for blasting and the potential applications of alternative energy forms, comminution depends entirely on conversion of electrical energy to motion in crushing or grinding machinery. The lowhead aspects of the tumbling mill, as well as the indirect nature of its energy transformations, suggest the possible use of other forms of energy that can be applied more directly for producing ore fragmentation.
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From page 69... ...
Nickel Flash and electric furnace smelting produce most of the nickel matte from sulfide concentrates; electric furnaces and leaching dominate lateritic nickel production. Converting of nickel matte is done pyrometallurgically in rotary converters.
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From page 70... ...
No new primary production processes for zinc have been developed since the l950s, although some modest work on decreasing energy requirements has led to pilot-scale trials of a hydrogen anode concept in West Germany. Lead Most of the world's primary lead is produced by the sinter-blast furnacekettle refining process.
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From page 71... ...
Circulating fluid bed roasting for processing refractory gold ore, a process adapted from alumina calcining technology, is under investigation for a major overseas project and will be compared to the autoclave processing alternative. Recent Hydrometallurgical Process Developments Copper Major increases in copper production have resulted from the use of solvent extraction/electrowinning processes in the United States and abroad.
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From page 72... ...
(Courtesy Magma Copper Mine.) Anaconda refinery cathode room, 1902.
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From page 73... ...
Lead Significant new developments in primary lead hydrometallurgy are under way in Italy, and plants treating secondary lead may soon be in operation in Europe and the United States.
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From page 74... ...
Significant R&D has continued into ways to decrease power consumption and improve electrode performance in the existing reduction process and to decrease emissions to the environment, with some success. Precious Metals Pressure oxidation of refractory gold ores appears to be the emerging technology of choice where roasting cannot be used.
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From page 75... ...
Further research into advanced reagents or designed organisms capable of extracting specific metals from underground deposits with a minimum of earth moving and waste production could revolutionize the minerals and metals industry. Before these techniques can be properly and universally applied to in situ extraction methods, however, extensive research is required in the areas of underground and surface fluid control, containment, and dewatering techniques.
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From page 76... ...
minerals and metals industry. Evolutionary advances that would improve the current state of exploration techniques are · improved spatial and spectral image resolution to penetrate foliage and surface cover; · increased digital geophysical coverage of the United States magnetically, gravitationally, radiometrically, and spectrally to one-half mile; and · improved drilling/sampling techniques and analytical methods to increase basic knowledge.
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From page 77... ...
Further research into advanced reagents or designed organisms capable of extracting specific metals from underground deposits, with a minimum of earth moving and waste production, could potentially revolutionize the field. Before in situ extraction methods can be properly and universally applied, however, extensive research is required in the areas of underground and surface fluid control, containment, and dewatering techniques.
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From page 78... ...
In Proceedings of the XVI International Mineral Processing Congress, K
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