METHOD OF BLAST-FURNACE SMELTING Russian patent published in 2000 - IPC

FIELD: ferrous metallurgy; blast-furnace process; iron smelting with use of neutral gas and oxygen. SUBSTANCE: charge material is charged into blast furnace, heated oxygen-enriched blast is put on, mixture of natural gas with oxygen is blown into air tuyeres, degree of use of gas (CO+H₂) in furnace is monitored and process oxygen is additionally blown into air tuyeres adjusting its flow rate in accordance with the following dependence: , where V_bl is rate of blast, cu. m/min; V_mix is flow rate of gas-and-oxygen mixture, cu.m/min; V_techn.ox is rate of flow of process oxygen to air tuyeres, cu.m/min; j is total degree of use of gas, fractions of unit; W is content of oxygen in heated blast, fractions of unit; N is preset relationship of (CO+H₂)/N₂ in blast-furnace gas. Relationship (CO+H₂)/N₂ in blast-furnace gas is maintained from 3.1 to 3.2 to obtain chemical raw material from blast furnace gas. EFFECT: reduced consumption of coke; enhanced consumers' properties of blast-furnace gas. 2 cl, 3 ex