增韧贫铁矿载氧体在化学链燃烧中的烧结特性OA

A kind of fiber-toughened Fe-based oxygen carrier(OC)was studied by long-term redox cyclic tests on a fluidized bed thermogravimetric analyzer for chemical looping combustion.Experimental results indicated that sintering began to occur in the OC after the 4th cycle during fluidized bed cycling tests,leading to agglomeration due to particle sintering.In fixed bed cyclic tests,despite using a smaller mass of bed material and low concentration of reactive gases,the OC particles still began to sinter after the 8th cycle,suggesting that sintering and agglomeration were inherent characteristics of the OC particles.Morphological features showed that the elemental iron in the particles melted at high temperatures and adheres to each other upon particle collision,with sintering spreading upwards from the bottom of the bed.Comparing the cyclic characteristics of Cu-based OC by crystallization granulation method,it could be seen that a lower melting point and excessively high oxygen carrying capacity were not the direct causes of agglomeration sintering.Therefore,the key to achieving large-scale industrial application of anti-sintering oxygen carriers lay in the particles with highly-dispersed active metal elements.