矿物质脱除对煤中硫在氢气热解中逸出的影响

Effect of Demineralization of Coal on Its Sulfur Evolution During Pyrolysis in H2 Atmosphere

对3种不同矿物质含量和硫含量的煤进行了脱除矿物质的实验,采用TG-MS对原煤和脱矿物质煤进行了AP-TPR实验,并在线分析了气相中主要的含硫化合物.结果表明:由于煤中矿物质种类的不同,在AP-TPR条件下对不同含硫气体的逸出有不同的影响.煤中矿物质的碱酸比越大,对煤的固硫作用越强;反之,对煤中有机硫醚和硫醇等C—S键的分解越强.煤中矿物质对COS的生成有很大的影响,高温时氢气抑制COS的生成,二次反应对COS的生成同样起重要作用.从原煤和脱矿物质煤噻吩硫的逸出峰分析得出,脱矿物质对煤中噻吩硫影响很小.

Three coals with different contents of mineral matter and sulfur were demineralized. Both the mineral-free coal and the raw coal were pyrolyzed in atmospheric H2 and the major sulfur-containing gases were detected by on-line MS. The results show that different mineral matters have a different effect on the evolution of sulfur compound in AP-TPR. The alkaline-earth mineral in the raw coal plays an important role for sulfur fixation under the AP-TPR condition, while the acid-earth mineral in coal can promote the decomposition of organic sulfur. At the same time, the mineral matters have a great effect on the formation of COS. At high temperature the hydrogen can suppress the formation of COS. The secondary reaction has an important effect on the formation of COS. According to the evolution of thiophenes from both raw coal and demineralized coal, it can be seen that the mineral matters have only a little effect on the stability of thiophene.