The developme~ of economic techniques of mining and concentrating taconite (fine• grained, Ierruginous jasperoids) led to the introduction of the iron-ore pellet, which is now becoming the major form in which iron is introduced into the furnace. The tre• mendous reserves of magnetic taconites of the northern United States and Canadian Precambrian shield had been recognized for many years. A century of mining has seen the reserves of the direct-shipping or "red ores" of the Minnesota, Michigan, and Wis• consin ranges approach depletion. Research started in the 1930s has seen the evolution of motives and techniques to concentrate these stubborn refractory ores. The efficacy of con• centrate pellets in- iron-making has been such as to induce mines throughout the world to grind, concentrate, and pelletize otherwise shipping-grade ores. Table 14.1A.1 shows • typical analyses of iron ore.
Ketersediaan
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Pusat Sumber Daya Mineral, Batubara dan Panas Bumi - Jln. Soekarno Hatta No. 444, Bandung, Jawa Barat
PMB LU 1976 - 1