| 摘要 |
The purpose of the present invention is to properly control the supply amount of a phosphorus removal solvent through a top lance in accordance with the supply amount of an oxygen gas through the top lance to perform a phosphorus removal reaction with high efficiency in the phosphorus removal treatment of a hot metal in a converter-type refining furnace. A phosphorus removal treatment method for removing phosphorus from a hot metal (18), which comprises blowing an oxygen gas against the hot metal (18) in a converter-type refining furnace (2) through a top lance (5) and spraying a CaO-type phosphorus removal solvent (20) against an oxygen-gas-impinging surface of the hot metal to thereby oxidize phosphorus contained in the hot metal with the oxygen gas, and then allowing a phosphorus oxide produced by the oxidization to be incorporated in the CaO-type phosphorus removal solvent. In the method, the amount of the CaO-type phosphorus removal solvent to be added is controlled in accordance with the amount of oxygen not to be used for silicon removal, wherein the amount(kg/hot metal-ton) of oxygen not to be used for silicon removal is defined as the amount of a portion of the oxygen gas to be supplied to the furnace, which is determined by subtracting the amount of a portion of the oxygen gas to be used in a silicon removal reaction from the amount of the oxygen gas to be supplied to the furnace, and wherein the above-mentioned control is performed in such a manner that the ratio of the amount (kg/hot metal-ton) of CaO in the CaO-type phosphorus removal solvent to be added by spraying onto the surface of a hot metal bath through the top lance to the above-mentioned amount of oxygen not to be used for silicon removal, i.e., [(amount of CaO)/(amount of oxygen not to be used for silicon removal)] becomes less than 0.90. |
