Control method for oxygen argon decarbonization converter end point temperature end point carbon

Abstract

The invention relates to a method for controlling endpoint temperature and endpoint carbon of an argon oxygen decarburization converter. An endpoint carbon and endpoint temperature mathematic model is constructed to achieve the best control effect. The model constructing steps comprise: (a) chemical components of C, Mn, Si, Cr, Ni and P of molten steel in the converter and the initial furnace condition temperature are read from basic automatic level; (b) according to data and mathematic models, a least square method is used for working out reaction rate constant Ki, activity coefficient Fi of components in liquid steel, mass transfer coefficient Ni of the components in the molten steel during the slag liquid phase reaction and equilibrium constants Kco, Kcr2o3 and Ksio2, and values worked out according to working conditions are written into a database during the automation of the production process; (c) the direct oxidation heat releasing in unit time of a reaction surface is worked out according to the models; (d) the temperature change of the molten steel and the concentration change of the components in the molten steel within the time step of delta t are worked out according to the heat balance in the converter. The method of the controlling endpoint temperature and the endpoint carbon of the argon oxygen decarburization converter prolongs the service life of the converter, reduces blow losses of chromium and achieves the function of removing carbon to protect chromium.

Description

technical field [0001] The invention belongs to the technical field of metallurgical refining outside the furnace for producing different steel types, and in particular relates to a method for controlling the end point temperature and end point carbon of an oxygen-argon decarburization converter (AOD). Background technique [0002] The basic principle of the oxygen-argon decarburization converter (AOD) process is to add hydrogen or nitrogen while blowing oxygen to the molten steel under normal pressure to decarburize, and reduce the partial pressure of carbon monoxide to achieve carbon removal and chromium preservation. In AOD smelting, the hit ratio of end point carbon and end point temperature is the key to affect AOD smelting. Only by controlling the end point carbon and end point temperature can the furnace life be increased and the loss of chromium reduced. [0003] At present, in most AOD factories, the endpoint carbon control is generally predicted with the help of e...

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Problems solved by technology

[0004] The task of the present invention is to provide a kind of oxygen-argon decarburization converter endpoint temperature and endpoint carbon control method, which solves the low degree of automation of the current AOD endpoint carbon control and endpoint temperature determination, which easily causes process instability and cannot improve the chromium recovery rate. And problems that are not conducive to converter maintenance

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