49.ガス化反応に伴う石炭チャー構造変化のHRTEM観察

抄録

In order to correlate the gasification reactivity of coal chars with their structure, raw and acid treated Pocahontas No.3 coal chars were gasified in 1% O_2 at 600℃. The structural changes in the coal chars during gasification reaction were quantitatively evaluated using HRTEM image analysis technique. Raw coal chars showed presence of highly crystalline portions in comparison with acid treated chars probably due to catalytic effect of mineral matters during the pyrolysis process. The lower crystallinity of acid treated chars can partly be correlated to their observed higher reactivity than raw coal chars. Raw coal char showed a clear increase in crystallinity during the later stage of gasification, which is partly due to the increase in the fraction of initially present highly crystalline portions as the less crystalline portions were lost by gasification reaction.