Method for slagging by utilizing return mine powder

Abstract

The invention discloses a method for slagging by utilizing return mine powder. The method for slagging by utilizing the return mine powder comprises the following steps of after a converter starts toblow for 2 to 3 minutes, adding 100 to 200kg of return mine powder into the converter; after the converter blows for 15 to 20 minutes, enter a blowing middle period, and adding 150 to 300kg of returnmine powder into the converter; appropriately increasing an oxygen lance position, so that the oxygen lance burn-leakage caused by violent reaction in the converter is avoided; after a flame at a furnace mouth is stabilized, slowly lowering an oxygen lance to the original position; and according to the slagging situation in the converter, appropriately repeating the steps of S2 to S4 for 1 to 2 times. According to the method for slagging by utilizing the return mine powder provided by the invention, an original high lance position slagging manner is replaced, and a few return mine powder is added for multiple times during the smelting process so as to generate endothermic reaction, so that the furnace temperature rise is retarded, meanwhile, the carbon oxygen reaction rate is reduced, theconsumption of FeO is reduced, a dephosphorization effect is maximally ensured, the fluidity of furnace slags is improved, a favorable deslagging effect is achieved, the situation of furnace slag re-drying is effectively relieved, the production accidents caused by oxygen lance dead burning, gas flue dead burning and oxygen lance opening leakage are reduced, and the production efficiency of the converter is effectively improved.

Description

Technical field [0001] The present invention relates to the technical field of converter smelting, in particular to a method for utilizing returned ore powdered slag. Background technique [0002] In the process of converter steelmaking and blowing, due to high oxygen pressure and low gun position, especially in the mid-stage of intense carbon oxidation, low TFe content leads to the precipitation of high melting point substances such as 2CS, 3CS, and MgO in the slag, making the slag change The thickened slag is poor and cannot cover the metal surface, which is called slag re-drying. The slag re-drying affects the progress of the molten pool reaction and the slag formation process, and high basicity slag cannot be formed in time. If the re-drying is serious, it will cause metal splashing and deteriorate the blowing process. If it is not treated in time, it will not melt until it is blown to the end. , Will greatly reduce the effect of desulfurization and dephosphorization, and ca...

AI Technical Summary

Problems solved by technology

However, as the furnace temperature rises, the carbon-oxygen reaction rate gradually intensifies, and it is not effective to relieve the slag from drying up only by increasing the lance position or low oxygen pressure, resulting in oxygen lance sticking to steel, flue sticking to steel, etc. Severe production accidents such as oxygen muzzle scraping and leaking

At the same time, long-term high gun position or low oxygen operation will lead to insufficient jet penetration, explosive splashing of slag stratification, affecting dephosphorization and desulfurization effects, and long-term soft blowing oxygen supply will seriously affect the production efficiency of the converter