Abstract:
The coal char gasification experiments with Na
2CO
3 as catalyst was investigated on TGA. The pore structure and apparent structure evolution characteristics of char were studied by scanning electron microscopy and pore structure and specific surface area analyzer. The influence of temperature (650-800℃), gasification agent (steam, CO
2) and sodium carbonate loadings (Na
+ loading amounts 2.2%, 4.4%, 6.6%) on the gasification reactivity of Shenfu bituminous coal (SF) and Zunyi anthracite (ZY) were investigated. The results show that the loading of Na
2CO
3 stimulates the development of pore structure in pyrolysis process. In the atmosphere of CO
2, there was a saturated catalyst capacity for SF and excessive catalyst loading could block internal pore structure of coal, leading to the decrease of gasification reactivity. ZY gasification reactivity increases with catalyst loading, and both SF and ZY gasification reactivity increase with the increase of temperature. In the atmosphere of steam, both SF and ZY gasification reactivity increase with the rise of catalyst loading and temperature. Na
2CO
3 is favorable for the decrease of reaction temperature and activation energy under the desired gasification rate.