LAUSR

Ferro-coke is prepared by the slight coking of coal and iron ore. It is a new type of fuel used for blast furnace ironmaking for the purpose of energy saving and emission reduction. However, with the increase of iron ore content, the metallurgical properties of ferro-coke gradually deteriorate. To fabricate high-strength ferro-coke, coal tar pitch was used as a binder in this study. The microstructure, cold drum strength, thermal crushing strength, gasification reactivity and gasification kinetics of this modified ferro-coke were systematically studied and compared with those of gas-coal coke and ferro-coke without binder. The results showed that the coal tar pitch could reduce the porosity of ferro-coke by 4.57 pct, enhance the adhesion of carbon matrix to minerals and increase the microcrystalline structure of ferro-coke. The cold drum strength of ferro-coke increased from 28.04 to 86.34 pct after adding coal tar pitch, while the thermal strength of ferro-coke during the gasification process rose by only 100 N. The coal tar pitch had little effect on the gasification reactivity of ferro-coke, so the activation energy of modified ferro-coke was still low. The first-principle calculation results revealed that the promotion of Fe on the ferro-coke gasification was attributed to the reducing role of Fe on the reaction energy of ketone group decomposition.