Method for distributing raw materials with high zinc content in blast furnace with bell-less top

Abstract

The invention discloses a method for distributing raw materials with high zinc content in a blast furnace with a bell-less top, which comprises the following steps of: (1) controlling ore batch weight to be greater than a critical value, and ensuring that the average thickness of ore at the furnace throat is 8 to 10 percent of the diameter of the furnace throat; (2) adopting a material distribution mode from a small angle to a large angle increasingly at distributor chutes on the furnace top, and ensuring that small particle burden and powder caused by mass flow particle segregation are distributed from the center of the blast furnace to a part 1/3 away from the edge of the furnace wall when a material tank discharges materials; (3) selecting double-ring single pile top large-angle distribution for ore and coke gears, distributing outer-ring ore according to the maximum angle, ensuring that the ore and coke angular difference is -2 degrees and the angular difference of the inner and outer rings of the ore and the coke is 6 degrees, controlling the materials distributed in the inner ring to account for 50 to 60 percent of the total burden, making the ring number of the outer ring distribution at least two, and ensuring that the outer-ring distribution pipe top covers the inner-ring distribution pipe top; (4) adopting a positive packaging and ore-coke unequal line packaging method; and (5) regularly performing tank turning operation on tank-combined blast furnace with the bell-less top, and controlling 4 to 5 tank turning cycle periods in a material column.

Description

technical field [0001] The invention relates to a blast furnace smelting process, in particular to a material distribution method for a bellless top blast furnace using raw materials with high zinc content. Background technique [0002] Affected by the international financial crisis, it is imminent for the iron and steel industry to reduce the cost per ton of iron. In this environment, the ironworks reduce the cost of raw materials through sintering and adding blast furnace gas bag dust to achieve the purpose of reducing the cost of pig iron. While the cost of raw materials is reduced, the quality of raw materials is also reduced. The most obvious impact is the increase of zinc content in raw materials. [0003] Zinc is a silver-white metal with a specific gravity of 7.133 g / cm3 at 20°C. The melting point of Zn is 419.5°C and the boiling point of Zn is 906°C. Zinc often exists in the ore in the form of ZnS, sometimes in the form of carbonate or silicate. After entering th...

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Problems solved by technology

Zinc escaped with gas can deposit in pipes and cause blockage

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