Method for controlling sulfur in smelting of 80-grade tire cord steel under large scrap ratio

The invention discloses a method for controlling sulfur in smelting of 80-grade tire cord steel under the large scrap ratio. The method comprises the following steps that molten iron is desulfurized; smelting is conducted in a converter; LF refining is conducted; and subsequent procedures are normally conducted. According to the method, by means of measures such as adding graphite carbon balls during smelting, controlling the tapping temperature and adopting a mode of changing the alkalinity of a refining slag during refining, when the 80-grade tire cord steel is smelted by the converter with the large scrap ratio of 25% or above, the requirement that the scrap ratio is 25% or above can be met, the sulfur content in final molten steel after smelting can be controlled to be 0.0055% or below, and the requirement of a user on the stranding and wire breaking rate when a 80-grade tire cord steel wire rod is drawn to 0.20mm-0.38 mm is better met. Stranding test statistics show that the wire breaking rate is obvious