基于铁基载氧体的无烟煤化学链燃烧过程中硫分布特性

Distribution of sulfur in chemical looping combustion of anthracite based on Fe-based oxygen carrier

在间歇式固定床反应器上,基于Fe_2O_3/Al_2O_3载氧体,研究了还原阶段反应温度和Fe_2O_3负载量对无烟煤化学链燃烧产物及S元素分布的影响。研究结果表明,含碳气体释放量随反应温度升高而增加,随Fe_2O_3负载量先增加后减少。产物中CO_2比例随反应温度升高先增加后减少,在850℃时达到最高(37.6%)。在实验条件下,未检测到SO_2生成。反应2 h时,载氧体中S元素的富集程度随温度和Fe_2O_3负载量升高而增加;5.5 h时,载氧体中S元素分布比例随温度升高而显著降低。利用SEM分析了载氧体表面微观形态结构。分析表明,Fe_2O_3负载量大于40%会导致载氧体轻微烧结。

In a batch fixed bed reactor,distribution of sulfur was studied during chemical looping combustion of anthracite based Fe2O3/Al2O3 oxygen carrier(OC).Reduction temperature and content of Fe2O3 were tested as variables.The work showed that the carbonaceous gas quantity increased with increasing temperature,while it increased first and then decreased with content of Fe2O3 improved.The proportion of CO2 reached the highest value 37.6%at 850℃and there were no SO2 detected at experiments.At 2 h,the occupation of sulfur in OC increased with improvement of both temperature and the content of Fe2O3.At 5.5 h,the occupation of sulfur in OC decreased obviously with improvement of temperature.Surface microstructure of reacted OC was also evaluated using a scanning electron microscope.The results showed that OC sintered gradually with increase of content of Fe2O3.