The invention discloses a preparation method for carbon extraction and
manganese consercation in medium-
manganese high-
phosphorus molten steel (Mn is 0.70-0.90wt%, Si is 0.25-0.45wt%, P is 0.120-0.220wt% and S is less than or equal to 0.040wt%) in converter steel making. By adopting the preparation method, processes such as
slag retention operation,
continuous casting slag application, little slagsmelting,
constant pressure gun conversion operation in the
smelting process, lowest gun position pressing operation in primary pouring of a converter, and
slag wash of whole-process steel
discharge,are integrated and created, rapid slag formation in the
smelting process is promoted,
smelting reaction kinetic and thermodynamic conditions are improved, excellent slagging and
phosphorus removal effects are achieved,
molten steel and slag splashing in the
smelting process is avoided, a MnO allocation concentration is effectively increased, reduction of the MnO at the medium stage of smelting ispromoted, secondary oxidation of Mn in
molten steel at the later smelting stage is reduced, furthermore, the content of residual Mn in the molten steel at a final point is remarkably increased (0.25-0.40wt%), the addition amount of a
manganese alloy in a deoxidation alloying process is reduced, the steel making
alloy consumption and alloying cost can be remarkably reduced, and the market competitiveness of products can be improved.