Characteristics of fine chars from fluidized bed gasification of Shenmu coal

The ash fusion characteristics, particle-size distribution and gasification reactivity of Shenmu coal (SM) fine chars from ash agglomerate fluidized bed gasification were explored by ash fusion point analyzer, scanning electron microscopy equipped with energy dispersive X-ray analysis (SEM-EDX), and thermo-gravimetric analyzer. The results show that the decrease in basic ingredients (e.g. iron and calcium) and the increase in acidic ingredients make the ash fusion temperature (AFT) of SM fine chars lower than that of SM. There is a wide particle-size distribution in SM fine chars, which shows a significant multi-peak distribution, and a large difference of the elemental distribution in fine char particles with different sizes. The moisture content is lower and ash content is higher in fine power than that in SM, respectively. SM fine char has higher surface area than that of SM char, and relatively rich in meso-pores and macro-pores, which results in its higher gasification reactivity than SM char.