On the degree of oxygen of metal bath with upper blow in the LD converter

The reasons and the degree of the existing assimilation by the converter bath of the blast stream of oxidizing gas (oxygen) for refining the melt during the purging pe-riod have been considered. It has been shown that the degree of oxygen absorption from the blast of a metal bath is related to the fact that the peripheral part of the oxygen jet is reflected lengthwise from the exit section of the nozzles to the surface of the metallic melt because of the converter gases counterflows in the converter gas space and the slag layer. As this takes place the degree of oxygen uptake due to these factors is reduced by 5-35% depending on the regime parameters, on the design of the blowing devices, the portable properties of supersonic jets in the high-temperature gas cavity of the converter with counter flows of converter gases and melt, on the height of the tuyere position above the metallic melt and etc. The assimilation process is also influenced by the interaction of the gas jet with the liquid melt at the top injection, which is different for different intensity of blasting and the height of the location of the lance - laminar, transient or turbulent. It is shown that the existing mode of transferring disturbances from the surrounding atmosphere into the jet affects the regime of gas interaction with the melt. Appropriate analytical relationships for the determination and examples of calculation of the degree of oxygen assimilation by a metal melt in 160-t and 350-t converters of the upper blast during the interaction of oxidant flows with converter gases and slagmetallic melt are given. It has been found that during the main blowing time, the degree of oxygen uptake increases with increasing blast intensity, oxidizer speed in the effective (isobaric) section, with increasing characteristic sizes (diameters) of the nozzles and reducing their number, with lowering the tuyere and decreasing the distance from the root of the escaping jets to the metal surface bath