How to remove the impurities in the slag washing process of molten steel with premelted refining slag, today we will learn about the removal process of inclusions in the slag washing process of premelted refining slag, so that you have a deeper understanding of the premelted refining slag of Pengda refractory

There are two main functions of premelted refining slag in slag washing

1. The original inclusions in the steel collide with the emulsified slag drops, which are absorbed and assimilated by the slag drops and are removed with the slag drops floating upward. When the slag is washed, the emulsified slag drops are strongly stirred with the liquid steel, so that the chance of contact between the slag drops and the original inclusions in the steel, especially the human particle inclusions, increases sharply. The interfacial tension between slag and inclusions is much less than that between molten steel and inclusions. According to the introduction, the wetting angle between slag and inclusion is 15 ° to 20 ° and the wetting angle between molten steel and inclusion is 120 ° to 170 ° so inclusions in steel are easily adsorbed by slag droplets collided with each other.

The premelted slag used in slag washing process (CaO-Al2O3 system is mostly used for different slag washing, white slag or lime brick slag for the same slag washing) are all oxide melts, and inclusions are also oxides, so the inclusions absorbed by slag are easy to dissolve in slag drops, and this melting process is called assimilation. The inclusion is assimilated by the slag drop, which makes the slag drop long and accelerates the floating process of the slag drop.

2. In the process of slag washing, the surface of emulsified slag droplet can be used as the nucleus of deoxidation reaction new phase. Since the free energy required for the formation of new phase is not increased much, the deoxidation reaction can be carried out at a low supersaturation. At this time, the deoxidation products are easily assimilated by slag drops and float up with the slag drops, so the amount of deoxidized products remaining in the steel is obviously reduced, which is the reason why slag washing steel is relatively pure.