2006 Volume 92 Issue 12 Pages 857-864
New cokemaking by blending of agglomerated coal particles was developed for making high strength and high reactivity coke. Agglomerated coal particles were produced by coating the slightly caking coal particles with caking coal particles. In the case of conventional cokemaking process, at the high blending ratio of the slightly caking coal, coke reactivity is raised, however, coke strength reduces. Cracks can be easily generated at the interface between coke textures, because the slightly caking coal particles have low fluidity at the carbonization and the semi-coke has high contraction.
The slightly caking coal particles (1-5 mm) coated with the caking coal were carbonized in coal blend. From microfocus X ray CT images, the generation of the cracks at the interface between coke textures was not observed. When the -0.5 mm of Ro =1.1% caking coal was used as a coating coal and the slightly caking coal (MF value; 2 ddpm) was used as a central coal, coke strength and coke size were enhanced. At 1373-1773K, the CO2 reaction rate of the coke blended with 20% agglomerated particles was higher than that of coke without adding agglomerated particles.