Iron ore concentrates

Agglomeration. Iron ore concentrates are often too fine to be used directly in ironmaking processes therefore they must be agglomerated. 

Most iron-ore-concentrating drums are applied ia a multidmm configuration in order to obtain maximum rejection of nonmagnetic particles. In cobbing service, two dmms are typical but as many as four have been used. These dmm concentrators incorporate a repulping box ahead of each dmm in order to provide the next dmm with a feed that can accomplish nonmagnetic rejection. 

FIG. 20-56 Ball- and rod-mill circuit. Simplified flow sheet of the Cleveland-Chffs Iron Co. Republic mine iron-ore concentrator. To convert inches to centimeters, multiply hy 2.54 to convert feet to centimeters, multiply hy 30.5. (Johnson and Bjotne, Milling in the Americas, Gordon and Breach, New York, 1964.)... 

The proper functioning of the disks and drums is possible only over a narrow range of the liquid content of the agglomerating charge, and very little flexibility is available in this respect. This limitation may lead to operational problems as, for instance, when the balling feed is iron ore concentrates from a filter press and is excessively moist. 

The curves in Fig. 22 were calculated by means of the above equation, the points being experimental values. Figure 24 (Kwauk, Wang, Li, Chen and Shen, 1985) shows empirical correlations for the constants e and ea for FCC catalyst, fine and coarse alumina, pyrite cinder and iron ore concentrate. 

Sieurin An early process for making sponge iron. Layers of iron ore concentrate, lime, and coal were heated in covered crucibles. 

R.A. Koski, Pelletizing of various iron ore concentrates and natural ores as practiced by the Cleveland-Cliffs Iron Company, in K.V.S. Sastry (Ed.), Agglomeration 77, AIME, New York, 1977, pp. 46-73. 

Experimental values for e and ea for five kinds of solid materials— FCC catalyst, fine alumina, coarse alumina, pyrite cinder, and iron ore concentrate—ranging in character from Geldart s Group A to weakly Group B, are shown in Fig. 58 (Li et al., 1982, 1981). The correlation could be fitted with the following empirical equations (Kwauk et al., 1985) ... 

Li, Y., Wang, F., Dai, D., Wang, Y., and Zhu, Q. Fast fluidization—Features of flow for iron ore concentrate, Research report (in Chinese), Institute of Chemical Metallurgy, Academia Sinica (1978). 

Top feed drum Iron ore concentrates 2 %-200 mesh 8 mesh top size 35 6300-7300 15 150... 

Soon after World War II, work on pelletizing was also taken up in Sweden under the direction of Jernkontoret. By 1950 it was clear that pelletizing was a practicable and commercially attractive method of agglomerating fine iron ore concentrates. The first commercial plants commenced operation in Sweden in the early 1950s. They had capacities of between 10000 and 60000t/y, but only 5 years later, large plants with capacities of several million tons per year each were being installed. ... 

Table 22 in Section 4.2.3.2 shows the importance of sintered ore for iron and steel making till today. However, iron ore concentrates from poorer ores became finer while, at the same time, higher quality requirements were imposed on blast furnace feeds. As discussed in Sections 4.2.1.3.2,4.2.1.4.2, and 4.2.3.2, this resulted in the development of balling and pelletizing in North America and Sweden, a technology that has quickly attained widespread acceptance throughout the world (see Section 4.2.3.2, Figure 352, and Table 22). More recently, the technology was adapted for other ores, too. ...

At about the same time, another agglomeration technique was in its first development stages in North America pelletizing of fine iron ore concentrates. Within two decades this technology became a multimillion ton per year industry on a worldwide scale (see Section 5.4.2). 

P. G. Kihlstedt, Agglomeration of iron ore concentrations into cold-bound balls , in Proceedings of Ninth International Mineral Processing Congress, Praha, CSSR, Vol. II, 1970, pp. 306-17. 

Eisele, T.C., Kawatra, S.K., and Ripke, S.J., Water chemistry effects in iron ore concentrate agglomeration feed. Miner. Proc. Extr. Metall. Rev., 26, 295, 2005. 

The method for solids transported in slurry form is called hydraulic transportation. Today there are long distance rubber lined pipelines carrying a variety of minerals such as coal, limestone, rock phosphate, copper concentrate, nickel refinery tailings, iron ore concentrates and tailings in various parts of the world. The most important slurry pipelines in operation around the world are given in Table 4.2. 

Grangold process using cement bond Iron ore concentrate... 

Fig. 6.8-10 The influence of the amount of bentonite in a well-mixed iron ore concentrate feed on green and dry pellet compression strengths [B.18]...

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