A converter for the production of steel by a blowing process from a substantially liquid raw material, in particular pig iron, includes several injectors which are dispersed in the sidewall of the converter about the converter inner circumference and directed towards the bath level for refining the pig iron. The injectors are designed as supersonic nozzle, which are surrounded by a ring nozzle forming an enveloping gas jet. The injectors are oriented at an angle of max. 43° in relation to the bath surface, with oxygen being introduced through the supersonic nozzle and a mixture of compressed air and natural gas being introduced through the ring nozzle. The jet pulse for the oxygen jet fed through the supersonic nozzle is dimensioned such that an infiltration of the oxygen jet into the melt bath is ensured.