考察了城市污泥与神府煤共气化过程中硫元素的挥发行为。结合X射线衍射(XRD)分析与热力学计算,讨论了含磷化合物对硫挥发行为的影响机理。实验结果表明:污泥中磷酸铝可与硬石膏发生反应,使混合物中硫元素在较低温度下挥发出来。当气化温度为900~1200℃时,污泥对硫元素挥发比例影响最为显著。当气化温度为1000℃时,含磷质量分数为0.5%与1.0%的污泥一煤混合物中,硫元素挥发比例较神府煤分别上升了19.2%和35.5%。当气化温度高于1300℃时,样品中大部分硫元素挥发出来,污泥对混合物中硫元素挥发比例影响不显著。
The volatilization of sulfur during co-gasification process of sewage sludge with Shenfu coal was investigated. Influence mechanism of phosphorus compounds on sulfur releasing was discussed based on X-ray diffraction (XRD) and thermodynamic calculation. The results show that aluminum phosphate from sewage sludge can react with anhydrite and then lead to the releasing of sulfur at low gasification temperature, especially between 900℃ and 1 200℃. Sulfur volatilization ratios of sludge-coal mixtures, which phosphorus mass fraction is 0. 5% and 1. 0%, are 19. 2% and 35. 5% higher than Shenfu coal respectively at 1 000℃. When temperature is higher than 1 300℃, most sulfur in mixtures volatilizes, and the influence of sewage sludge on sulfur volatilization ratio is not significant.