Patent DE-102008049121-B3 (DE)
Title: Producing steel melt with manganese content, by producing crude steel melt in oxygen lancing converter, preheating manganese quantity in further oxygen lancing converter, and combining preheated manganese quantity with crude melt
Inventor: FELDHAUS BERND
IPC: C22C33/04
Filed: 2008-09-27
Granted: 2010-02-25
Abstract: The method for producing a steel melt with manganese (2 wt.%), comprises producing a crude steel melt, whose manganese-germanium content lies below the required limit, in an oxygen lancing converter, and preheating a quantity of manganese in a further oxygen lancing converter at a temperature, which is less than a melting temperature of the manganese, even so high that is not fallen below the melting temperature of the manganese during subsequent mixing of the preheated quantity of manganese with the crude steel melt contained in the further oxygen lancing converter. The method for producing a steel melt with manganese (2 wt.%), comprises producing a crude steel melt, whose manganese-germanium content lies below the required limit, in an oxygen lancing converter, preheating a quantity of manganese in a further oxygen lancing converter at a temperature, which is less than a melting temperature of the manganese, even so high that is not fallen below the melting temperature of the manganese during subsequent mixing of the preheated quantity of manganese with the crude steel melt contained in the further oxygen lancing converter, where the preheated quantity of manganese is sufficient in relation to the crude steel quantity melted in the oxygen lancing converter used for melting the crude steel melt to adjust the required manganese content of the steel melt to be produced in the converter, combining the preheated quantity of manganese with the crude steel melt, and intermixing the preheated quantity of manganese with the crude steel melt, so that the manganese melts and mixes itself with the crude steel melt to the steel melt having the required manganese content. The manganese quantity is preheated in the oxygen lancing converter, whose refractory lining is heated by a preceding steel producing process. In case, that more than a passage of the production of high manganese-containing steel melt is completed, the assignment of the both oxygen lancing converters are exchanged after each passage, so that the required manganese quantity is preheated in the converter, in which the crude steel melt is melted in the first completed passage, and the crude steel melt is melted in the converter, in which the required manganese quantity is preheated in the first completed passage. The temperature of the refractory lining is 1500[deg] C. A fuel is additionally introduced to the manganese quantity for preheating the required manganese quantity in the converter and burns in the converter. The fuel is introduced in the form of a coke and/or a flammable gas in the converter. The manganese-fuel-mixture that is filled in the further converter used for preheating the manganese quantity is admitted with oxygen. The oxygen is blown in the manganese-fuel-mixture over nozzles provided in the base of the converter, and is blown to the manganese-fuel-mixture over an oxygen blowing lance introduced in an opening of the converter. The blowing of oxygen takes place by the oxygen blowing lance time-delayed for blowing the oxygen over the nozzles. During the blowing of oxygen, the flammable gas is introduced in the converter. The further oxygen lancing converter is pivoted for intensificating of intermix of the manganese-fuel-mixture and for improving the combustion of the fuel during preheating. The preheated manganese quantity is evacuated from the further converter into a hot pig iron ladle and is delivered by the pig iron ladle into the further converter filled with the pig iron melt. The pig iron melt is evacuated from the converter into a hot pig iron ladle and is delivered by the pig iron ladle into the further converter filled with the preheated manganese quantity. The crude steel melt and the preheated manganese quantity are delivered into the pig iron ladle and are mixed with one another in the pig iron ladle.