TUYERE STOCK ARRANGEMENT FOR A BLAST FURNACE AND METHOD FOR FEEDING HOT BLAST INTO A BLAST FURNACE

摘要

Tuyere stock arrangement (10) of a blast furnace comprising a tuyere (14) having a tuyere body (20) configured for installation in a blast furnace wall (12); the tuyere body (20) having an outer wall (22), a front face (24) and a rear face (26), the tuyere body (20) further having a tuyere channel (28) extending from the rear face (26) to the front face (24), the tuyere channel (28) forming an inner wall (30) in the tuyere body (20). The tuyere stock arrangement (10) further comprises a blowpipe (34) connected between the rear face (26) of the tuyere body (20) and a gas feeding device (38), the blowpipe (34) being configured and arranged so as to feed hot gas, generally hot blast air, from the gas feeding device (38) to the tuyere channel (28) for injection into the blast furnace. The tuyere stock arrangement (10) also comprises an injection lance (40) for feeding a combustible, generally pulverized or granular coal, into the blast furnace at the tuyere level, the injection lance (40) being an coaxial lance comprising an outer pipe and an inner pipe, coaxially arranged within the outer pipe, the outer and inner pipes being arranged for separately conveying oxidizing gas and said combustible, the inner pipe forming a separation wall for separating said combustible from the oxidizing gas. According to an important aspect of the invention, the injection lance (40) is removably arranged in a lance passage (42) formed in the tuyere body (20), the lance passage (42) being arranged between the inner wall (30) and the outer wall (22) of the tuyere body (20) and extending from the rear face (26) to the front face (24), the lance passage (42) opening into a front face (24) of the tuyere body (20).