The sulfur content in high-grade non-oriented silicon steel W310 is generally required to be less than 0.002 5%. Based on the manufacturing process of " KR― BOF—>RH—^continuous casting

the mechanism of KR deep desulphurization

converter smelting and RH powder spraying desulphurization are analyzed and studied in this paper

combined with the working conditions and raw material conditions of the 300 t steel-making system

the thermodynamic and kinetic conditions improvement measures such as optimization of hot metal composition and temperature

composition adjustment of KR and RH desulfurizer

converter heal balance control

strong bottom blowing smelting and process sulfur load control are put forward. Application results show that after optimization

the ratio of sulfur content less than 15 x 10

-6

in once KR treatment has increased from 69% to 100%

and the sulfur content after treatment has decreased from 10.48 x 10

-6

to 7.07 x 10

-6

. The average sulfur content at the end point of converter is 20. 10 x 10

-6

and sulfur pick-up by 13.03 x 10

-6

during process

which are 44. 8% and 49. 8% lower than before optimization

respectively. The sulfur content of RH liquid steel decreases from 19.50 x 10

-6

to 8. 65 x 10

-6

the dosage of desulfurizer decreases by 55.9%

and the proportion of sulfur less than 25.00 x 10

-6

increases from 90.5% to 100%

good results have been achieved.