Optimization Study Of LF Process In Jiuquan Iron & Steel Corp.

Metallurgical effects of LF refining in Jiuquan Iron & Steel Corp., such as deoxidation and desulphurization, has been always much poorer since LF equipment was built in 1997. Based on sufficient field investigation and demonstration, the study succeeded in optimizating on-line LF process by strengthening condition of thermodynamics and dynamics. Parameters of bottom Ar-blowing have been optimized by means of hydraulic model experiment. New synthetic refining slag and new process were adopted in study of the subject. Refining functions of LF were exploited by industrial tests. Good effects of deoxidation, desulphurization and inclusion removing was achieved.Rounded analysis and evaluation of traditional process of LF in Jiuquan Iron & Steel Corp. have been done in this paper and problems of traditional process were founded. In the tests the problems have been modified.Results of hydraulic model experiment and Industrial tests indicated that Ar flux should change according to different phases of refining period.Industrial tests also indicated that refining slag of CaO-Al2O3 and CaO-BaO can get good effects of deoxidation and desulphurization.the quantity of refining slag required is 1.6% of weight of molten steel,.The average heating power is 5800~6200KW. Time of Ar-blowing is 30-42min. The average of Ar-blowing time is 35min.Study of the subject draw a conclusion that LF of Jiuquan Iron & Steel Corp. has had the condition of well deoxidation and well desulphurization. If process was optimizated and equipment was modified, obvious refining effects wound must be realized.