Flux additions, refining and deslagging procedures for the production of very low phosphorus and sulphur steels in oxygen converters when processing low silicon iron
A series of experiments has been carried out in a 3 tonne pilot plant converter to examine the effect of various flux combinations on removing sulphur and phosphorus from low silicon, 0.3%, hot metal. The fluxes used have been lime, fluorspar, dolomet, alumina, calcium ferrate and iron ore. The latter has also been used as a coolant. The other major process parameter used in the study was basal gas stirring of the liquid metal. Pretreatment of the hot metal with certain flux combinations was also performed. As well as pilot plant experiments physical modelling studies have been carried out to determine whether gas stirring in the converter barrel could assist in removing slag from the converter during slagging operations. In the final phase of the experimental programme the parameters were optimised in a series of heats in the pilot plant converter. It was found that the pretreatment period with the lime, alumina, fluorspar flux mixture was not required and addition at the start of the blowing period achieved the desired effect. An overall basicity of seven was still needed but increased gas stirring was unnecessary at the end of the blowing period. It was found that the removal of dolomet from the system was also an advantage. Using iron ore as a coolant gave good phosphorus removal and did not affect sulphur.
Bibliographic Reference: EUR 12007 EN (1988) MF, 90 pp., ECU 4, blow-up copy ECU 11.25
Record Number: 198910373 / Last updated on: 1994-12-01
Original language: en
Available languages: en