Abstract: To solve the problem of high nitrogen content at the endpoint of semi-steel steelmaking converter in Pangang Group Xichang Iron & Steel Co., Ltd., the variation and influence factor of nitrogen during blowing have been carried out. And then, control measures of nitrogen mass fraction were raised, such as controlling the scrap consumption, reducing reblowing, using custom-made bottom blowing system and charging foaming agent. Application effect indicated that by using these technologies, the average nitrogen mass fraction at the end-point of 200 t converter was reduced from over 18×10-6 to less than 13×10-6, and nitrogen mass fraction less than 15×10-6 was carried out. The technology has been widely use during the production of low nitrogen steel, which provide technical support for the production of low nitrogen steel.

Key words: steelmaking with semi-steel, nitrogen concentration, the end of the converter