Method for removing inclusions in vacuum of RH single molten steel

The invention discloses a method for removing inclusions in vacuum of RH single molten steel. The method comprises the following steps that (1), the vacuum degree of a vacuum system is controlled to be 6-8KPa at the initial stage of RH vacuumizing; (2), 50-80kg of dried high-calcium limestone is weighed from a stock bin to a vacuum hopper; (3), the weighed high-calcium limestone in the vacuum hopper is fed into a vacuum tank through an alloy chute; (4), it is observed that the CO2 concentration in a waste gas analyzer reaches the level before the first batch of high-calcium limestone is added;and (5), the operation of b, c and d is repeated for 3-4 times. According to the method for removing the inclusions in vacuum of the RH single molten steel, raw materials are easy to obtain, the costis low, after the high-calcium limestone is rapidly decomposed in the high-temperature molten steel, a large amount of CO2 is generated, in the upward floating and overflowing process, tiny inclusions are promoted to collide