2014 Volume 54 Issue 12 Pages 2697-2703
Influences of preparation technologies on properties of straw char (corn) and its use as a supplementary fuel for coke breeze in iron ore sintering were investigated. By means of one-stage carbonisation, produced straw char achieved similar volatile and fixed carbon contents to coke breeze, where recommended carbonisation temperature was 700°C, heating rate was 10–25°C/min, and carbonisation time was 30 min. Two-stage carbonisation, consisting of one low temperature stage and the other high temperature stage, facilitated the further removal of volatile matters, and making straw char increased in yield and fixed carbon content. Recommended one-stage carbonisation benefited reducing combustibility difference between straw char and coke breeze since densified strucuture was achieved. Compared with one-stage carbonisation, two-stage carbonisation made straw char more densified in structure and less difference in combustibility to coke breeze. For straw char prepared from one-stage and two-stage carbonisation, recommended replacement ratio to coke breeze were 20% and 40% respectively. The emission reduction of SOx for replacement ratio 20% and 40% were 10.98% and 38.15% respectively, and that of NOx were 12.67% and 22.53% respectively.