Converter steelmaking fluoride-free composite fluxing medium

The invention relates to a converter steelmaking fluoride-free composite fluxing medium, which belongs to the treatment of molten iron alloy by adopting a finishing agent to remove foreign matters. The invention particularly relates to a quick fluxing medium for converter smelting, which consists of the following ingredients in percentage by weight: aluminum oxide (Al2O3): 25 to 45 percent; ferric oxide (Fe2O3): 15 to 35 percent; boron oxide (B2O3): 3 to 10 percent; magnesium oxide (MgO): 5 to 15 percent; calcium oxide (CaO): 3 to 15 percent; and the balance of foreign matters and caking agent. The fluxing medium presents in granular pellets and are filled into a furnace in two times at the beginning of the converter smelting, and 6 to 8 kg of the fluxing medium is added per ton steel. Compared with the prior art, the converter steelmaking fluoride-free composite fluxing medium has the advantages that: no calcium fluoride (CaF2) is contained, so the pollution of the atmosphere and thewater resource caused by