A kind of molten iron pretreatment desiliconization/dephosphorization agent and using method thereof

Abstract

The invention discloses a desiliconization / dephosphorization agent for molten iron pretreatment, which is formed by mixing high-iron red mud and lime particles at a mass ratio of 1: (0.2-0.3); the TFe content in the high-iron red mud is 40-0.3 50wt%, the particle size of high-iron red mud is 0.088-0.5mm. The particle size of the desiliconization / dephosphorization agent is ≤3mm, wherein the content of the desiliconization / dephosphorization agent with a particle size of 1-3mm is ≤5wt%. The invention also discloses a method for using the molten iron pretreatment desiliconization / dephosphorization agent. The steps are as follows: according to the requirements of steelmaking and smelting steel types and the conditions of molten iron entering the station, it is determined whether to perform desiliconization alone, dephosphorization or both operations. conduct. When the high-iron red mud of the present invention is used as a desiliconization / dephosphorization agent for pretreatment of molten iron, it can avoid slag foaming and prevent slag from overflowing from the molten iron furnace, and has good desiliconization and dephosphorization effects.

Description

technical field [0001] The invention relates to a molten iron pretreatment desiliconization / dephosphorization agent and a using method thereof, belonging to the technical field of molten iron pretreatment in the iron and steel metallurgical industry. Background technique [0002] In the iron and steel metallurgical industry, the pretreatment process of molten iron is mainly to provide molten iron with stable composition and low phosphorus and sulfur content for the steelmaking process, so as to facilitate the operation and control of steelmaking and improve the economical efficiency of steelmaking. Therefore, it focuses on desiliconization and dephosphorization of molten iron and desulfurization in three aspects. The methods adopted mainly include powder spraying method, KR stirring method and so on. [0003] The desiliconization of molten iron pretreatment mainly utilizes the strong oxidizing property of silicon, and removes by adding solid iron oxide into molten iron: ...

AI Technical Summary

Problems solved by technology

But in the composition of the molten iron pretreatment agent mixture of this patent, CaO / SiO 2 All above 3.0, the purpose is to create a hot metal pretreatment agent with high alkalinity to achieve desiliconization, desulfurization and dephosphorization of hot metal, but such a high alkalinity pretreatment agent is not needed in the desiliconization process, and causes The high viscosity of the desiliconization slag can easily cause serious slag foaming, overflowing the reaction vessel, and causing production and safety accidents; secondly, with such a high alkalinity pretreatment agent, it is difficult to melt the slag during the pretreatment process, reducing the efficiency of desulfurization and dephosphorization. does not guarantee

The red mud used has not been treated for iron purification, and it needs to be added with Fe 2 o 3 Mixing to increase the total iron content of the pretreatment agent to ensure the oxidation ability of the pretreatment agent increases the cost

And the patent uses a small amount of red mud, which only accounts for 15-30% of the ratio of the molten iron pretreatment agent

In addition, the production method of this patent needs to combine red mud with Fe 2 o 3 , CaO, NaCO 3 , MnO 2 , CaCl 2 , SiO 2 or other metallurgical wastes containing these components are mixed and ground, with many types of ingredients and complex process ratios

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