中文摘要：

以水蒸气为气化剂、Fe_4Al_6（Fe_2O_3：Al_2O_3质量比4：6）为载氧体,在高温间歇流化床中添加神木煤灰模拟串行循环流化床,研究煤灰累积对煤焦化学链气化过程中载氧体反应性能及结构的影响.结果表明,在800~900℃的化学链气化过程中,添加5%~15%（w）神木煤灰可降低Fe_4Al_6载氧体还原反应的温度、提高其还原反应速率.添加15%神木煤灰可明显促进煤焦水蒸气气化,提高煤焦碳转化率.Fe_4Al_6载氧体还原反应温度为950~1000℃、系统中含20%神木煤灰及1000℃、系统中含15%神木煤灰时,神木煤灰易与Fe4Al6载氧体反应生成Fe_2SiO_4,Fe Al_2O_4,Ca Fe_4Al_2O_（10）和CaAl_8Fe_4O_（19）等低熔点物质,使Fe_4Al_6载氧体孔堵塞、表面烧结.

英文摘要：

The influence of coal ash accumulation content on the reaction between Shenmu coal char and Fe_4Al_6 oxygen carrier（Fe_2O_3： Al_2O_3 mass ratio 4：6） and the oxygen carrier microstructure by adding Shenmu coal ash was investigated in a laboratory-scale fluidized bed.The results showed that addition 5%~15%（w） ash can reduce the reduction reaction temperature of Fe_4Al_6 oxygen carrier and increase the reaction rate between oxygen carrier and coal char at the temperature of 800~900 ℃.Carbon conversion rate curve was fit by Gaussian peak fitting method,indicating that 15% ash can promote the char gasification stage and increase the carbon conversion rate.It found that low-melting-point compounds,such as Fe_2SiO_4,FeAl_2O_4,CaAl_8Fe_4O_（19） and Ca Fe_4Al_2O_（10） formed in the oxygen carrier with 20% ash at 950~1 000 ℃ of reduction reaction temperature of Fe_4Al_6 oxygen carrier and with 15% ash high than 1 000 ℃.The compounds with low melt point and low thermal conductivity may attribute to the sintering and agglomeration of the Fe_4Al_6 oxygen carrier.