CAJ | 학술논문

利用 CaO-SiO2熔渣去除冶金级硅(MG-Si)中的杂质硼。热力学分析和实验结果表明：纯 SiO2基本上不能去除冶金级硅中的杂质硼。通过建立硼的分配系数与熔渣中 SiO2和 CaO 活度之间的关系，从热力学上对CaO-SiO2熔渣的除硼能力进行表征。结果表明：随着渣中CaO配比的升高，硼的分配系数和去除效率大大提高。当熔渣组成为60%CaO-40%SiO2(质量分数)时，硼的分配系数达到最大值1.57。当渣硅比为2.5，精炼温度为1600°C以及精炼时间为3 h时，利用60%CaO-40%SiO2熔渣可以将冶金级硅中的硼含量从18×10-6降低至1.8×10-6，去除效率达到90%。
이용 CaO-SiO2용사거제야금급규(MG-Si)중적잡질붕。열역학분석화실험결과표명：순 SiO2기본상불능거제야금급규중적잡질붕。통과건립붕적분배계수여용사중 SiO2화 CaO 활도지간적관계，종열역학상대CaO-SiO2용사적제붕능력진행표정。결과표명：수착사중CaO배비적승고，붕적분배계수화거제효솔대대제고。당용사조성위60%CaO-40%SiO2(질량분수)시，붕적분배계수체도최대치1.57。당사규비위2.5，정련온도위1600°C이급정련시간위3 h시，이용60%CaO-40%SiO2용사가이장야금급규중적붕함량종18×10-6강저지1.8×10-6，거제효솔체도90%。
Boron removal from metallurgical grade silicon (MG-Si) using a calcium silicate slag was studied. The results show that it is impossible basically to remove boron using a pure SiO2 refining. The oxidizing ability of CaO-SiO2 slag for boron removal was characterized by establishing the thermodynamic relationship between the distribution coefficient of boron (LB) and the activities of SiO2 and CaO. The experimental results show that the distribution coefficient and the removal efficiency of boron are greatly improved with the increase of CaO proportion in the slag. The maximal value of LB reaches 1.57 with a slag composition of 60%CaO-40%SiO2 (mass fraction). The boron content in the refined silicon is reduced from 18×10-6 to 1.8×10-6 using slag refining at 1600 °C for 3 h with a CaO-SiO2/MG-Si ratio of 2.5, and the removal efficiency of boron reaches 90%.