BAOSHEREX (Baosteel-Shenghua high efficiency smelting reduction) ironmaking process for smelting molten iron by two-step method

Abstract

The invention provides a BAOSHEREX (Baosteel-Shenghua high efficiency smelting reduction) ironmaking process for smelting molten iron by a two-step method, which belongs to the technical field of ironmaking. The steps of the process comprise vertical furnace type prereduction; and additional arrangement of a melt gasification furnace outside a vertical prereduction furnace: oxygen gas and pulverized coal are sprayed from oxygen gas tuyeres which are uniformly distributed in the middle part of a furnace cylinder of the melt gasification furnace, and generated heat meets the requirements of generating molten iron and furnace slag. In the BAOSHEREX ironmaking process, coal accounts for 80-85 weight percent of fuel, only oxygen gas containing 500-600m<3> / t of iron and carbon coke accounting for 15-20 weight percent of the fuel are used for producing high-quality hot molten iron at a temperature of 1350-1480 DEG C, pelletized water granulated slag and high-quality coal gas. The BAOSHEREX ironmaking process has the advantages of high yield, high efficiency, low energy consumption, low emission and low cost.

Description

technical field [0001] The invention belongs to the technical field of ironmaking, and in particular relates to a BAOSHEREX ironmaking process for smelting molten iron in two steps. Water production capacity and high equipment utilization. Background technique [0002] The technology of the modern blast furnace ironmaking process has been developed for hundreds of years. At present, great progress has been made in many aspects such as high output, low consumption, longevity, efficiency, high quality, and environmental protection. It is currently the world's absolute dominant ironmaking craft. [0003] However, the strong dependence of the blast furnace ironmaking process on high-quality metallurgical coke and high-quality artificial lump ore makes it very difficult to develop ironmaking production in areas lacking coke. Therefore, it is determined that it must have a long process from coking, sintering or pelletizing to the blast furnace; it is determined that it needs to ...

AI Technical Summary

Problems solved by technology

[0008] ⑴The pre-reduction shaft furnace completely relies on the coal gas produced by the melting and gasifier to produce pre-reduction iron, and the production capacity can only reach 70% of the design capacity, which makes the fixed cost of molten iron remain high

[0009] (2) When the pre-reduction shaft furnace is connected with the melter gasifier, 20% of the produced gas will be washed with water and then used to cool the produced gas and adjust the temperature to 840°C, losing the "golden gas" medium temperature of the produced gas between 1050°C and 850°C Heat, which increases the energy consumption of reduction smelting

[0011] ⑷Both furnace top gas and cooling gas are purified and cooled by water washing, dedusting, and cooling, which produces a certain amount of phenol-cyanide-containing wastewater, which increases environmental load and treatment costs

[0012] ⑸Reduced gas contains about 15-20% hydrogen, and top gas contains CO+CO 2 75% or more, the CO emitted per ton of molten iron 2 Emissions are lower than blast furnaces, but still higher

[0014] FINEX has the following main disadvantages: (1) Pre-reduction fluidized bed using 0-10mm fine ore and gas containing up to 60% CO, due to the heat release of CO reduction reaction in the reducing gas, the local temperature in the fluidized bed is higher than the temperature of entering and exiting the furnace Between 50°C and 80°C, the fluidized bed will often cause material cohesion and loss of flow and be forced to shut down the furnace for treatment, and the equipment utilization rate of the fluidized bed is not high

(2) Iron powder with a metallization rate of 60% produced by FINEX fluidized bed must be hot briquetted to make briquette iron before use. The maintenance cost of hot briquetting equipment is high, so the processing cost of briquette iron is high

(3) FINEX fluidized bed reduction has high requirements on the reducibility of iron ore, which limits the selection range of iron ore and increases the cost of raw materials

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