METHOD OF SINTERING LOW-BASIC SINTER Russian patent published in 2001 - IPC

FIELD: metallurgy, particularly, processes of raw materials preparation for blast-furnace practice. SUBSTANCE: method involves successive supply to moving sintering cars of two layers of sinter burden of different thickness and with different content of solid fuel and moisture in each layer; subsequent ignition of burden and creation of rarefaction under sintering cars. Speed of movement of sintering cars in the course of sintering is set by relationship: V = K x Qi.o.c. x Tu.l. x Wl.l. x P/Tl.l. x Hu.l. x B, where V is speed of car movement, m/min; Qi.o.c. is consumption of iron ore component of burden, kg/t of sinter burden; Tu.l., Tl.l. are values of solid fuel consumption in upper and lower layers, respectively, kg/t of sinter burden; Wu. l., Wl.l. are values of moisture content in upper and lower layers, respectively, %; Hu. l. , Hl.l. are values of thicknesses of burden upper and lower layers, respectively, mm; P is rarefaction under sintering cars, mm H₂O; B is required basicity of ready sinter equalling 0.5-0.7, dimensionless; K is empirical coefficient characterizing burden sintering rate in both layers equalling (8,5-80)·10^-7 m.t/min.kg(mm H₂O). In this case, thickness of burden lower layer is set within 0.2-0.8 of total thickness of burden layers. Iron ore component is used in the form of slime, mixture of iron-or concentrates, sinter siftings, mill scale. Consumption of each component is set within ranges of (0.05-0.13), (0.7-0.8), (0.11-0.12) and (0.03-0.065), respectively, from total iron-ore component of sinter burden. The proposed method provides conditions for production of sinter with low basicity of 0.5-0.7. EFFECT: higher efficiency. 2 cl, 1 tbl