refining slag has been carried out by using orthogonal experimental method. With variance analysis and significance criterion it is obtained that the optimum ingredient of the pentatomic refining slag is 25% Al
2
O
3
12% CaF
2
7% MgO and R2 ( CaO/SiO
2
) =2.5. And the regression analysis is carried out by using SPSS software to get the math relationship equation between ingredient with high reliability and melting temperature of refining slag: T