高铁高钙煤灰载氧体反应动力学特性及改性研究

Analysis on the reaction kinetics and modification of high iron and calcium coal ash as the oxygen carrier

运用TGA在CO/空气的氛围下,对灰的循环反应性能进行测试。通过动力学分析,对灰的循环反应能力进行更深入评价。最后,对灰进行重新造粒并用流化床进行实际应用能力检测。结果表明:灰的表观活化能为27—38 kJ/mol,且具有良好的循环反应能力。在TGA实验中,重新造粒获得的载氧体(Ash7-ATP3),其释氧量约为12%—14%,且在多次循环过程中释氧量基本保持不变。在流化床实验中,Ash7-ATP3的释氧量与TGA实验结果相似。分析每次循环后颗粒质量分数可知,5次循环过程中颗粒大小基本为0.5—1 mm,约保持在97%,具有良好的稳定性。

The circulation ability of ash was investigated by thermal gravimetric analyzer(TGA)with CO or air.Through kinetic analysis,the cyclic reaction capability of ash was further evaluated.Finally,the ash was re-granulated and tested for practical application using fluidized bed.The results show that the apparent activation energy of ash is 27-38 kJ/mol,and it has good cyclic reaction ability.In TGA experiments,the oxygen release of re-granulated oxygen carrier(Ash7-ATP3)is about 12%-14%,and the oxygen release is stable during multiple cycles.In the fluidized bed experiments,the amount of oxygen released by Ash7-ATP3 is similar to the results of TGA experiments.After analyzing the particle content after each cycle,it can be known that the particle size during the five cycles remained 0.5-1 mm,and the particle mass of 0.5-1 mm accounts for 97%of total mass of the oxygen carrier after each reaction.