Abstract: In order to achieve high-efficiency sulfur fixation in the roasting process of high-sulfur coal gangue， industrial waste boron mud was used as the sulfur fixation agent to conduct sulfur fixation experiments on coal gangue. In view of the deficiency of single factor test， the Box-Behnken response surface method was used to study the effects of sulfur fixation agent dosage， roasting temperature， roasting holding time， etc. on the sulfur fixation rate of coal gangue. The interaction between the factors was clarified. The research results show that when the mass ratio of magnesium in the sulfur-fixaing agent to the sulfur in the coal gangue is 9， with a roasting temperature of 620℃， and a roasting holding time of 100min， the sulfur-fixaing rate of the coal gangue reaches 89.35%.The most influential factor on sulfur fixation in coal gangue is the amount of sulfur fixation， followed by the roasting temperature， while the roasting holding time(within 2h)has little effect. There is a significant interaction between the roasting temperature and the amount of sulfur fixation. The optimized coal gangue sulfur fixation process can provide certain technical support for the resource utilization of high-sulfur coal gangue.

Key words: high-sulfur coal gangue; boron mud; roasting sulfur fixation; Box-Behnken test design; response surface optimization