摘要
采用CaO-SiO2-10%CaF2渣系,对工业硅进行造渣除硼研究。研究不同工艺条件下,渣系碱性、反应温度T、渣金比和通气搅拌对硼在渣相和硅液中分配系数LB的影响。结果表明,在1873K下,当CaO/SiO2质量比为2时硼的分配系数可达最大值4.61。在1773～1973K下,lgLB与1/T成线性关系。随着渣金比的增大,硼的分配系数也相应增大,但当渣金比大于3时,硼的分配系数并无明显增加。通气可显著提高硼的去除效果,硼的分配系数随气体中H2O含量的增加而增大。
The removal of boron from metallurgical silicon in slag system of CaO-SiO2-10%CaF2 was investigated. The partition coefficient of boron （LB） between slag and silicon phase was studied under different conditions of slag basicity （CaO/SiO2 ratio）, temperature, mass ratio of slag to silicon and gas blowing. The results show that LB has a maximum value of 4.61 when the CaO/SiO2 mass ratio is around 2 at l 873 K. The logarithm of LB is linear to the reciprocal of temperatures in the range of 1 773-1 973 K. LB increases with the increase of mass ratio of slag to silicon, but it does not increase markedly when the ratio excesses 3. Gas blowing can sionificantlv increase the removal of boron, and LR increases with the increase of water vapor content.
基金
Project(2007J0012)supported by the Natural Science Foundation of Fujian Province,China
Project(2007HZ0005-2)supported by the Key Technological Program of Fujian Province,China
关键词
太阳能级多晶硅
造渣
除硼
分配系数
solar grade silicon
slag treatment
boron removal
partition coefficient
