Method for producing low-sulfur molten iron in one step by smelting and reducing copper slag

Abstract

The invention discloses a method for producing low-sulfur molten iron in one step by melting and reducing copper slag. The method is characterized in that the method includes the following processing steps that: the high-temperature molten copper slag is first reduced by reducing agent in a high-temperature reduction furnace, wherein, when the reduction reaction of iron is nearly finished, a certain amount of additive, which is theoretically calculated, is added in a melting bath based on the existing slag system in the reduction furnace, a jet gun is inserted into a slag-iron interface to blow carbon monoxide into the melting bath when the additive is completely molten, the blowing time is 30min to 40min, and desulphurization reaction is almost finished. The melting bath is kept still, and when slag and iron are completely separated, the high-temperature low-sulfur molten iron and the slag are respectively discharged out of a tap hole and a slag hole. In addition, after high-temperature flue gas passes through a secondary combustion chamber, a residual heat boiler recovers residual heat from the flue gas, dust is collected from the flue gas by cyclone, and the flue gas is washed. By sufficiently utilizing the high desulphurization of the refined slag and blowing the carbon monoxide, the invention solves the defect that the content of sulfur in the molten iron produced by melting and reducing the copper slag for ironmaking is high; the processing flow is short, the emission of pollutant is less, and moreover, the applicability is high.

Description

technical field [0001] The invention relates to a method for preparing low-sulfur molten iron in one step through copper slag smelting reduction, which belongs to the field of resources and environment. Background technique [0002] In recent years, China's iron and steel industry has developed rapidly. my country's iron and steel industry occupies a pivotal position in the world's iron and steel industry. For more than ten years, its total iron and steel production has always occupied the first place in the iron and steel industries of all countries in the world. However, my country's iron ore resources are far from meeting the needs of the iron and steel industry, and the distribution of resources has the following characteristics: first, there are many lean ores, and the reserves of lean ores account for 80% of the total reserves; The third is that my country's iron ore resources are scarce, the grade is low, and the production capacity of steel enterprises across the coun...

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Problems solved by technology

[0008] 2. Iron is enriched in magnetite through oxidation roasting-crushing magnetic separation process. This process has the disadvantages of low iron recovery rate and complicated follow-up treatment process

However, this process has the disadvantage of high sulfur content in molten iron after copper slag smelting reduction (average content higher than 0.6%)

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