高灰煤小型流化床混合气催化气化研究

在内径28mm流化床中，对阳泉高灰煤在碱性催化剂（固碱和黏胶废碱液）作用下进行了混合气（空气/水蒸气）催化气化研究，两种碱性催化剂的适宜添加量均为6％。不加催化剂，气化温度830℃~900℃与900℃～920℃下，气化反应的表观反应级数n分别约为2/3与1/3；有催化剂（3％固碱）时，表观反应级数有两个明显的温度段，在830℃~860℃，催化气化的表观反应级数n=1；在860℃~920℃，催化气化的表观反应级数为n=1/3。

Investigation on catalytic gasification of high-ash coal with mixing-gas in a small-scale fluidized bed

The experimental study on the Yangquan high-ash coal catalytic gasification with mixing-gas (air/steam) by using solid alkali (sodium hydroxide) or waste liquid of viscose fiber as the catalyst in a small scale fluidized bed with 28mm i.d. was carried out. The loading saturation levels (LSL) of two catalysts in Yangquan high-ash coal are about 6%. Under the gasification temperature ranging from 830℃ to 900℃ and from 900℃ to 920℃, the apparent reaction order of Yangquan high ash coal with respect to the unreacted carbon fraction approximates to 2/3 and 1/3 for the non catalyst case, respectively. Also, the different values of apparent reaction order in the two temperature ranges are presented for the case with 3% solid alkali catalyst loaded. At the low temperature ranging from 830℃ to 860℃, the apparent reaction order of catalytic gasification is 1 since enough active carbon sites on the coal surface are formed during the catalytic gasification by solid alkali. But at the high temperature ranging from 860℃ to 920℃, the sodium carbonate produced by the reaction of solid alkali with carbon dioxide can be easily fused, transferred and re distributed, which affects the gasification reaction rate, and the apparent reaction order of catalytic gasification is reduced to 1/3.