The method of determination of the reactivity (CRI) and strength of coke after its high-temperature interaction with CO_2 (CSR) proposed by the Japanese company Nippon Steel has become the dominant method for the determination of the quality of blast-furnace coke. There have been determined the optimal values of CRI and CSR: <32 and >58 percent, respectively [1]. It has been recognized that the level of these indices has a significant effect on the operating characteristics of the blast furnace. As the CSR level increases the extent of breakdown of coke diminishes, the permeability of gases and liquids in the fusion zone of the furnace is improved, the furnace output increases and the specific consumption of coke for smelting of pig iron decreases.In order to produce a coke of the required level of the parameters CRI and CSR, investigations have been carried out in a number of countries with a view to establishing the most essential factors that affect the formation of the carbon skeleton of coke stable towards chemical-thermal influences. Most of the investigators have come to an agreement that such factors are genetic factors inherent only in the coal material and technological factors, i.e., conditions for the preparation and carbonization of the coal blend. The genetic factors include the vitrinite reflectance index, the maceral composition and plastic properties of coal organic matter (COM) and also the contents of Fe_2O_3, CaO and SO_3 in the ash moiety. The technological factors include the bulk density of the charge being carbonized, the rate of its heating, the final coking temperature and the condition of the ovens [2-7].
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