Common splashes in converters are mainly divided into explosive splashes, foam splashes and metal splashes.

1 Causes of explosive splashing

The carbon-oxygen reaction in the molten pool develops unevenly, and a large amount of CO gas is instantaneously generated, which is the root cause of explosive splashing.

Carbon-oxygen reaction: [C]+(FeO)={CO}+[Fe] is an endothermic reaction, and the reaction rate is affected by the carbon content of the molten pool, the content of slag (TFe) and the temperature. Due to operational reasons, the molten pool is suddenly cooled, suppressing the intense carbon-oxygen reaction; the oxygen produced by the human being generates a large amount (FeO) and accumulates; when the temperature of the molten pool rises again to a certain extent (generally at 1470 ° C) Above), when (FeO) accumulates to more than 20%, the carbon-oxygen reaction proceeds again at a more violent speed, and a large amount of CO gas with a large amount of energy is instantaneously discharged from the furnace mouth, and at the same time, a certain amount of molten steel and slag are carried. , formed a large splash. In the case where the slag is too oxidized and the bath temperature suddenly rises and then rises, explosive splashing may occur.

2 causes of foaming splashes

In addition to the oxidation of carbon is not balanced, there are factors such as furnace capacity ratio, slag amount, slag foaming and other factors can also cause splashing.

When the content of Si and P in molten iron is high, the content of SiO2 and P2O5 in the slag is also high, and the slag amount is large. In addition, the content of TFe in the slag is high, and the surface tension is lowered, which hinders the smooth discharge of CO gas, and thus the slag layer The expansion is thickened and can rise to the mouth of the furnace when it is severe. At this time, as long as there is a small thrust, the slag will be ejected from the mouth of the furnace, and the molten metal entrained by the slag will also come out to form a splash. At the same time, the foam slag covers the molten pool and has a hindrance to the discharge of gas. Severe foaming slag may cause the furnace to overflow. Obviously, when the amount of slag is large, it is easy to produce splashing; if the furnace capacity is larger than that of the converter, the furnace space is also large, and the possibility of large splash is relatively small.

3 reasons for metal splashing

When the TFe content in the slag is too low, the slag is thick, and the molten pool cannot be returned to the covering liquid surface in time after being blown away by the oxygen flow. The discharge of the CO gas is carried out by the metal droplets to fly out of the furnace mouth to form a metal splash. The slag "back to dry" also produces metal splashes. It can be seen that some of the reasons for the formation of metal splashes are exactly the opposite of explosive splashes.