铁矿--生物质复合球团还原行为及还原动力学

通过分析生物质合成气气氛下，不同组分复合球团(添加和未添加生物质)的还原速率、还原度、表面微观结构和失重变化规律，对球团中添加生物质的作用机理以及含生物质球团还原过程的限制性环节展开研究.添加生物质的复合球团表面结构比无生物质球团疏松，孔隙率高，有利于后续还原的热质传递，增加产物还原度，降低反应活化能；复合球团的还原以收缩核方式进行，在1123~1323 K温度范围内，界面化学反应是两种球团还原反应的主要控速环节；添加生物质后，有利于界面化学反应的进行，使得球团的还原表观活化能由95.448 kJ·mol-1降低到68.131 kJ·mol-1.

Reduction behavior and reaction kinetics of iron ore--biomass composite pellets

The reduction reaction rate, reduction degree, surface microstructure and weight loss of composite pellets with different components under biomass syngas atmosphere were investigated to illustrate the effects of biomass addition in pellets on the reduction behavior and reaction kinetics. The porosity of pellets with the addition of biomass is higher than that without the addition of biomass, which is favorable to heat and mass transfer of the reduction process, increases the reduction degree of products and decreases the apparent activation energy of reaction. The reduction of pellets was carried out in the manner of a shrinking core model. In the range of 1123 to 1323 K, the rate-controlling mechanism of reduction for these two kinds of pellets is interfacial chemical reaction. The addi-tion of biomass in pellets can improve the interfacial chemical reaction, and thus the apparent activation energy of reaction decreases from 95. 448 kJ·mol-1 to 68. 131 kJ·mol-1 .