Method of Bottom Blowing and Powder Spraying in Converter to Improve Effect of Gasification Dephosphorization

Abstract

The invention provides a method for improving the gasifying dephosphorization effect through bottom-blowing powder spraying of a converter. The method for improving the gasifying dephosphorization effect through bottom-blowing powder spraying of the converter specifically comprises the steps that after steel is discharged out of the converter, the basic state of converter slag is observed and judged, slag-splashing converter protection operation is started, and gasifying dephosphorization powder is sprayed into the converter through a carrier gas nozzle at the bottom of the converter at the same time; the bottom-blown carrier gas pressure and the powder-gas ratio of the converter are controlled, so that the gasifying dephosphorization powder efficiently reacts with hot slag in the converter under the surging and stirring effect achieved when the carrier gas penetrates through the converter slag; and phosphorus in the slag is removed in a gasifying mode, the slag is converted into gasified and dephosphorized high-quality slag after the reaction and is used for the next round of converter smelting. The gasifying dephosphorization rate of the converter is 50%-60%, the penetration ratio of the dephosphorization powder is 80%-90%, and lime consumption is reduced by 2.5-3.5 kg / t. According to the method for improving the gasifying dephosphorization effect through bottom-blowing powder spraying of the converter, the strong surging and stirring function and other functions of the gasifying dephosphorization powder and the carrier gas are brought into full play, the gasifying dephosphorization rate is increased, the slag-splashing converter protection cycle is shortened, and the utilization rate of left converter slag is increased. The bottom-blowing dephosphorization powder is not prone to being carried away, the operating condition and distribution of the powder in the hot slag are improved, and the utilization rate of the powder is increased.

Description

technical field [0001] The invention belongs to the new technology of converter steelmaking and its application field, in particular to a method for improving the gasification dephosphorization rate of a converter and making full use of converter bottom blowing powder spraying of converter hot slag to improve the effect of gasification dephosphorization. Background technique [0002] Converter slag is a by-product of converter steelmaking. Since the molten iron needs to be dephosphorized during the converter smelting process, the phosphorus element in the molten iron is basically oxidized into phosphorus pentoxide and enters the slag. Therefore, the converter slag contains a large amount of phosphorus. How to dephosphorize the molten iron? The removal of phosphorus from recovered slag and the further recycling of converter slag have always been a research hotspot. [0003] In the late 1970s, Japanese scholar Ito Gongjiu studied the Ca in the converter 2 SiO 4 -Ca 3 (PO 4...

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Problems solved by technology

[0007] These patented methods can effectively gasify dephosphorization, but the reactants of these patents, whether it is powder and slag, or gas and slag, are added from the upper part of the converter, and the gasification dephosphorization rate is still low due to the influence of kinetic conditions. To achieve the value calculated by thermodynamics, how to further improve the kinetic conditions and strengthen the rapid, sufficient and efficient contact reaction between powder and slag and gas and slag needs to find new ideas

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