Thermodynamic analysis of reducing MgO content in slag for blast furnace A in Shougang
WANG Dong- qing1,2,MA Ze- jun1,2,CHEN Hui1,2,WANG Wei1,2,ZHU Wei- chun1,2
1. Beijing Key Laboratory of Green Recyclable Process for Iron and Steel Production Technology,Beijing 100043, China 2. Institute of Iron and Steel Department, Research Institute of Technology, Shougang Group Corporation, Beijing 100043, China
Abstract：With the trend of large- size of blast furnace, the higher demands for the slag property, especially the mobility and stability in high temperature were put forward in production. The appropriate melting temperature and viscosity were required for the blast furnace smelting. Based on the thermodynamic software FactSage, the effects of the MgO content on the liquidus temperature and viscosity of the slag for blast furnace A of Shougang were analyzed. The results showed that liquidus temperature is about 1 400 ℃ of the slag for blast furnace A, and the slag was fully liquid and had a good mobility. The slag composition was in the liquid phase region at 1 500 ℃. If reducing the MgO content, the slag was still in the liquid phase region. When the MgO mass fraction was in the range of 2.87%- 7.37%, the liquidus temperature increased with the increase of the MgO content. And when increasing the MgO mass fraction of 1%, the slag liquidus temperature increased 3.73 ℃. The slag viscosity reduced with increasing the MgO content. And the slag viscosity reduced 0.014 Pa·s with increasing the MgO mass fraction of 1%. It was considered when the hearth heat condition was good(hot metal temperature above 1 480 ℃), reducing the MgO mass fraction to 6% had little impact on the slag viscosity. But when the hearth heat condition was bad(hot metal temperature is below 1 480 ℃), reducing the reduction of the MgO content was not recommended.
2018, Vol. 28 
