吴家坪煤在流化床热解过程中含硫气体产物的分析

在氧气体积分数分别为3.0%、5.6%、 8.7%的O2 N2混合气，热解温度500℃～800℃, 停留时间30min下，对吴家坪煤在流化床反应器热解过程中的含硫气体进行了分析。热解过程中主要的含硫气体是H2S、COS和SO2, 且它们的逸出规律一致：随着温度和氧气体积分数的增高, 逸出速率加快。 氧气体积分数对煤中的H2S、COS的影响是相似的, 随着氧气体积分数增加, 相对于3.0% O2 N2 气氛, H2S和COS的逸出量占气相中总硫的比例在5.6% O2 N2 气氛下降, 在8.7% O2 N2 气氛下又有所上升; 而氧气体积分数对SO2的影响与之相反, 在5.6% O2 N2 气氛下, 气相中93%以上是以SO2形式逸出的, 在8.7% O2 N2 气氛下, SO2的比例又下降很多。这是由于8.7% O2 N2 气氛下, 更多的氧气参与了C—C键断裂的反应, 使脱去的硫转化到焦油中，从而也生成了大量的CO，使得在8.7% O2 N2气氛下CO/SO2比明显大于5.6% O2 N2气氛下的。

Sulfur-containing gases analysis during pyrolysis of Wujiaping coal in fluidized bed reactor

Wujiaping coal pyrolysis was investigated in a fluidized bed reactor under atmospheres of 3.0%, 5.6% and 8.7% O2 N2 at the temperatures ranging from 500℃ to 800℃ and the residence time of 30min. GC and flue gas analyzer were used to measure the sulfur containing gases . It is found that the main forms of sulfur containing gases are H2S, COS and SO2, which have similar evolution rule: the evolution rate increases quickly with increasing temperature and oxygen content. The ratio of H2S and COS to the total sulfur amount in pyrolysis gas decreases much under 5.6% O2 N2 compared with that under 3.0% O2 N2, however, under 8.7% O2 N2, it increases greatly. But the effect of oxygen content on SO2 evolution is contrary to that of H2S and COS. Under 5.6% O2 N2, above 93% of total sulfur in the pyrolysis gas is SO2, but under 8.7% O2 N2 the ratio decreases remarkably to 56%. This suggests that under 8.7% O2 N2, more oxygen takes part in the reactions of C—C bonds cleavage, which results in the formation of more CO and higher ratio of CO/SO2 than that under 5.6% O2 N2.