Converter melting slagging method

The invention relates to a converter melting slagging method. The method comprises the following steps: step one, after smelting is started and an oxygen lance is ignited, adding a converter flux in two batches, wherein the converter flux is lime and light-burned dolomite, the first batch of converter flux is added for two to three times after the oxygen lance is ignited, and the lance height is controlled to be 150 to 180 cm; step two, after the oxygen lance blows oxygen for 2 to 3 minutes, adding the second batch of converter flux for two to three times, and after the last convert flux is completely added, adopting a lance height of 280 to 300 cm; step four, after 5 to 8 minutes of converter blowing, reducing the lance height to 150 to 180 cm; step five, after 10 to 12 minutes of blowing, lifting the lance height to 280 to 300 cm; step six, executing a catch-carbon lance height of 120 cm until the blowing finishes, wherein the catch-carbon time is not less than 2 minutes; and step seven, taking out the oxyg