In situ experimental study of CO2 gasification of petcoke particles on molten slag surface at high temperature

The gasification reaction of petcoke on wall slag layer was an important issue that should be studied during the co-gasification process of coal and petcoke. In present work, the gasification characteristics of petcoke particles on molten slag surface was investigated using a high temperature stage microscope. The catalytic effect of slag on petcoke gasification on slag surface was demonstrated. The experimental results demonstrated that the catalytic effect of slag only worked when the particle was on the surface of slag. The catalyst vapor had no influence on the reactivity of petcoke. What's more, the SEM analysis result showed that the reaction surface area of petcoke was decreased as a result of the deposition process. The effect of molten slag on particle temperature could be neglected as a result of the weak endothermic effect. Therefore, the change of petcoke reactivity rely on the synergy between catalytic effect of slag and the decreased reaction surface area. Besides, the increased residence time of petcoke also could increase the carbon conversion compared with that in gasifier chamber.

Automated summary

The gasification reaction of petcoke on the wall slag layer is an important issue during the co-gasification process of coal and petcoke. The catalytic effect of slag on petcoke gasification on slag surface was demonstrated, but only effective when the particle is on the surface of slag. In addition, the increased residence time of petcoke can increase the carbon conversion compared with that in the gasifier chamber, indicating the importance of synergy between catalytic effect of slag and decreased reaction surface area.