Since the phosphorus content in hot metal at Shuisteel is up to 0. 104% ~ 0. 157%

the 30

#

~ 80

#

SWRH82B

ER70S-6

SWRCH22A and 40Cr etc high quality steels are melted by 100 t top and bottom combined blown converter using double-slag operation to reduce the phosphorous content in liquid

in this case the metal consumption is 1 054 kg/t and the lime consumption is 32. 4 kg/t. Based on the analysis o£ thermal equilibrium of single-slag process

increasing early slag dephosphorizing ability

optimization of slagging schedule in middle and latter period and oxygen supply schedule

and optimization of furnace capacity ratio

the single-slag deep dephosphorization process for high quality steels is established. The application results show that metal consumption for melting high quality steels decreases to 1047 kg/t

the lime consum

ption decreases to 29. 4 kg/t

the tapping [C

]

= 0. 14% ~ 0. 28% and the tapping [P

]

= 0.014%〜0.020%.