采用湿式混合成粒法得到了一种复合型钙基载氧体,并分别在综合热分析仪和流化床上考察了其反应活性和循环反应性能。结果如下:浸渍Ni离子能够明显降低载氧体与煤反应的起始温度,加快反应速率,缩短反应时间。增加 Ni离子浸渍量对反应速率的影响不明显,但反应时间略有缩短。选择 CaAlNi10载氧体进行了10次还原-氧化循环实验,固体产物和气体产物分析表明NiO在循环过程中对S的释放有一定控制作用;CaAlNi载氧体具有较高的再生率和良好的持续循环反应能力。结果表明,制备的CaAlNi载氧体适用于工业生产。
In this test,one kind of Ca-based compound oxygen carrier was prepared by chemical impregnation and further processed by extruding granulation device. The method is characterized by simple operation and high yield,which was suitable for large-scale preparation of oxygen carrier. An investigation into the reduction reactivity between compound oxygen carriers and the coal was carried out in TGA and a fluidized bed,respectively. The reaction rate for the compound oxygen carrier impregnated with nickel nitrate,reacting with coal was much faster than that for fresh CaSO4 oxygen carrier. The reaction between CaAlNi oxygen carrier and coal took place at a lower temperature than that between fresh CaSO4 oxygen carrier and coal. Increasing the immersing amount of Ni ions has no effect on the reaction rate,which shortens the reaction time slightly. Experiment of CaAlNi10 oxygen carrier and coal was carried out in a fluidized bed by ten redox cycles. Further,it showed that NiO was able to capture S which released by CaSO4.The CaAlNi10 oxygen carrier particles were featured by the high reactivity and regeneration rate and excellent cycling stability in the fluidized bed during ten redox cycles. Therefore,the CaAlNi oxygen carrier is appropriate for industrial production.