烧结矿应用于化学链燃烧的反应特性  

Reaction characteristics of sintering ore used as an oxygen carrier in chemical looping combustion

作　　者：曹欢[1] 刘训良[1,2] 温治[1,2] 楼国锋[1,2] 

机构地区：[1]北京科技大学机械工程学院,北京100083 [2]北京科技大学冶金工业节能减排北京市重点实验室,北京100083

出　　处：《工程科学学报》2015年第4期422-428,共7页Chinese Journal of Engineering

基　　金：国家自然科学基金项目(51276015);中央高校基本科研业务费专项资金资助项目(FRF-SD-12-007B)

摘　　要：本文通过热重实验研究了烧结矿作为载氧体的H2还原反应特性,将其与通过溶解法制备的Fe2O3/Al2O3载氧体进行了氧化还原反应性比较,在500-1250℃范围内研究了温度对于烧结矿还原反应过程的影响,在950℃下进行了30次循环反应实验,采用四种模型进行了反应动力学分析.结果表明,烧结矿的H2还原转化率大于80%,可以完全再氧化,并具有良好的循环反应性能.在500-950℃范围内,随温度升高还原反应速率及最终转化率都显著增加;而当温度高于1100℃时,在反应后期还原反应速率和最终转化率有下降的趋势.在500-950℃范围内,对烧结矿的还原过程第一反应阶段（Fe2O3-Fe3O4/Fe O,还原转化率〈25%）可采用二阶反应模型（M2）拟合,得到表观活化能为E=36.018 k J·mol-1,指前因子为A0=1.053×10-2s-1;第二反应阶段（Fe3O4/Fe O-Fe,还原转化率〉25%）采用收缩核模型（M4）拟合,得到的表观活化能为E=51.176 k J·mol-1,指前因子为A0=1.066×10-2s-1.The reduction kinetics of sintering ore used as an oxygen carrier in the chemical looping combustion was experimentally investigated by thermogravimetry. The redox reactivity of sintering ore was compared with that of self-made Fez O3/AIO3 oxygen carriers prepared by the dissolution method. Experiments were conducted on the reduction of sintering ore by diluted hydrogen during the temperature range of 500 to 1250 ℃, and 30 cycles of redox reaction experiments were performed at 950℃. Experimental data was anlyzed by four kinetic models. It is found that sintering ore can be used as an oxygen carrier with a reduction conversion larger than 80% , complete oxidization, and a good performance of recyclability. The reduction reaction rate and final fractional conversion of sin- tering ore both increase with rising temperature from 500 ℃ to 950 ℃, while both have a trend of decline when the temperature is above 1100 ℃. The second order reaction model （M2） can properly fit the experimental data of the reduction of sintering ore in the first reaction stage （ Fe2 03 -Fe3 OJFeO, reduction conversion X 〈 25% ） during the temperature range of 500 to 950 ℃, achieving the apparent activation energy E = 36. 018 kJ. mol -1 and the pre-exponential factor A0 -- 1. 053 x 10-2 s -1 , whereas the shrinking core model （M4） fits well in the second reaction stage （Fe30/FeO-Fe, reduction conversion X 〉 25% ）, achieving the apparent activa- tion energy E = 51. 176 k-1 tool- and the pre-exponential factor Ao = 1. 066x 10 -2 s-

关 键 词：烧结矿 化学链燃烧 反应动力学 动力学模型 热重分析 

分 类 号：TF046.4[冶金工程—冶金物理化学]