微型流化床中气氛对还原度的影响

为了过程优化和提高反应的还原度,设计了两步法试验。试验采用的是微型流化床反应器,能够确保反应器空间中的每一个颗粒都处于相同的温度和气体浓度。试验结果表明,预还原阶段形成的颗粒表观形貌对还原度有着重要的影响,终还原阶段中的CO在混合气体中所占的比例直接影响着还原速率的大小。合理的控制还原反应速率,延长反应时间,有利于还原度的提高。当CO在混合气体中所占的比例为83%时,巴西矿粉的还原度达到了88%。

Effect of Atmosphere on Degree of Reduction in Micro-Fluidized Bed

To process optimization and improve the degree of reduction, a two-stage experiment was designed. It was carried out in micro-fluidized bed. It was operated as a differential reactor to ensure every particle in micro-fluidized bed being in equal temperature and concentration. The tests shows that the surface morphology in pre-reduction stage has an important effect on degree of reduction and the proportion of CO of gas mixture in final reduction stage has an important effect on rate of interfacial reaction too. Selecting reasonably chemical reaction rate and prolonging the residence time could be benefit to increase the reduction degree. When proportion of CO of gas mixture is equal to 83%, the reduction degree of brazilian ores could reach 88%.