Molten iron desilication method for stainless steel smelting

Abstract

The invention provides a molten iron desilication method for stainless steel smelting, which comprises the following steps: 1. blast furnace molten iron preparation: mixing and sintering laterite-nickel ore, adding the laterite-nickel ore into a blast furnace, and smelting while ensuring the blast furnace tapping temperature to be at least 1350 DEG C; 2. transportation: transporting the high-temperature nickeliferous high-silicon molten iron of the blast furnace to a desilication converter in the one-step or metal mixer form; 3. carrying out desilication, decarburization, dephosphorization and desulfurization on the nickeliferous high-silicon molten iron in the desilication converter, and carrying out desilication treatment on the molten iron in a top / bottom blowing mode, wherein the mass percent of silicon in the desilicated molten iron is not greater than 0.20%; and 4. final product smelting: after finishing converting, charging the semisteel from the desilication converter into an AOD (argon oxygen decarburization) furnace while adding alloy into the AOD furnace, and finishing the final smelting of stainless steel. The desilication technique has low requirements for Si content in the molten iron, provides sufficient reaction space for desilication, effectively prevents splashing, creates favorable dynamic conditions for desilication, and meanwhile, can perform dephosphorization and desulfurization.

Description

technical field [0001] The invention relates to a method for desiliconizing molten iron for stainless steel smelting, in particular to nickel-containing and high-silicon molten iron produced by treating laterite nickel ore. Background technique [0002] With the rapid development of the stainless steel industry, the demand for metal nickel continues to increase. However, nickel sulfide ore resources are increasingly scarce, making laterite nickel ore the main source of nickel supply in the future. Laterite nickel ore accounts for 72.2% of the world's land-based nickel resources, but the nickel it produces only accounts for 42% of the world's nickel production. Using laterite nickel ore to produce nickel iron water provides a cheap nickel source for the rapidly developing stainless steel industry. It is the use of laterite nickel ore efficient access to resources. The content of silicon in blast furnace ferronickel water produced from laterite nickel ore is very high, some a...

AI Technical Summary

Problems solved by technology

Combined with the characteristics of high content of nickel-containing molten iron [Si] and [Ni], the melting point of nickel is high. High nickel content leads to high tapping temperature of blast furnace. Limited desiliconization capacity; desiliconization in molten iron tanks is prone to splashing

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