LAUSR

In hot-metal dephosphorization treatment, fast dissolution of lime into molten slag is an important subject because dephosphorization treatment is performed at relatively low temperatures of approximately 1 573 K, which is the thermodynamically preferred temperature for the dephosphorization reaction. Fluorite is well-known as a useful solvent that promotes the dissolution of lime into molten slag. However, the use of fluorite is not preferable from the viewpoint that fluorine-containing slag comes to be restricted for its recycling usage or application. Moreover, the content of free-CaO in the slag is required to decrease for the usage of environmental resources. Consequently, fast dissolution of lime into the molten slag has become increasingly important. Several studies have attempted to clarify the dissolution mechanism of lime in molten slag and the increase in the dissolution rate of lime. For example, many researchers1–3) have reported that a 2CaO·SiO2 layer is formed around lime during its dissolution into molten slag; this layer prevents further dissolution of lime. Noguchi et al.4) reported that the high content of FeOx in the CaO–SiO2–FeOx slag promotes Influence of P2O5 on Dissolution Behavior of Lime in Molten Slag