INCREASING THE EFFICIENCY OF CO AFTERBURNING IN OXYGEN-CONVERTER PRODUCTION DUE TO THE USE OF MULTI-TIER TUYERES

In the oxygen-converter shops of metallurgical enterprises of Ukraine, which include PJSC “ArcelorMittal Kryvyi Rih”, PJSC “Dniprovsky Metallurgical Plant”, PJSC “KAMET-STAL”, in order to meet the world’s modern technological level, there is a need for the introduction of innovative construction of top tuyeres, which wills allows: expand the possibilities of controlling the blowing of melt; to improve the thermal balance of melting; to increase the degree of afterburning {СО} to {СО2} in the waste gas mixture; increase the rate and amount of introduction of solid charge materials if necessary. In this regard, the melt blowing technology using a multi-tiered top tuyere was developed and tested in laboratory conditions according to the principles of high-temperature physical modeling on a large-scale copy of a 160-t converter. The use of a multi-tiered tuyere made it possible to achieve, increase in the proportion of afterburning {СО} to {СО2} in the mixture of waste converter gases, from 14 % to 28 % compared to a two-tier tuyere. The formation of torches afterburner was be place with a flame propagation temperature of up to 3000 °С and an accompanying release of heat which is 565 kJ/mol O2, of which up to 65 % could be transferred to the metal melt with organization favorable conditions for the blowing in the working space of the converter bath. The processing of the results of high-temperature physical modeling made it possible to establish, among other things, the effect of changing the height of the slag-gas-metal emulsion on the nature of the formation of afterburning torches {СО} to {СО2} in the mixture of waste gases under the conditions of blowing with supersonic and sonic oxygen jets emanating from the nozzles of the multi-tier tuyere. On the basis of the received information and data from the experiments, was be developed of the regimes concept for afterburning {СО} to {СО2}. According to this conception, four main afterburning regimes are distinguished: Free afterburning mode; Arbitrary afterburning mode; Mode of internal-surface afterburning; Mode of intra-volume afterburning. Bibl. 31, Fig. 6, Tab. 1.