Refining slag and preparing method and application method of refining slag

The invention discloses refining slag, a preparing method and an application method of the refining slag. The refining slag comprises, by mass percent, 52.7%-72.7% of calcite powder, 27.3%-47.3% of alumina powder and the balance impurities. The preparing method of the refining slag includes the following steps that calcite and the alumina powder are weighed according to a proportion and are machined and ground to the particle size range of 0 mm-3 mm; the obtained calcite powder and the obtained alumina powder are mixed and stirred, a bonding agent is added in the stirring process, and briquette materials are formed; and a briquette machine is adopted for pelletizing, baking is conducted after screening, and the refining slag is finally obtained. The refining slag and molten steel can be mixed to be flushed to rapidly form molten slag or the refining slag can be added into a refining furnace to rapidly form foam slag on the surface of the molten steel. The refining slag, the preparing method and the application method of the refining slag have the beneficial effects that a certain amount of CO2 is brought in the manner of calcite, the foam slag is rapidly formed under the conditionthat a foaming agent is not added, submerged arc operation is conducted, in addition, the formed foam slag has high alkalinity and high purity, and good thermodynamic and kinetic conditions are provided for S removing and O removing of low-oxygen-steel molten steel.