低活性无烟煤固定床二氧化碳催化气化反应动力学研究

The catalytic gasification kinetics of low active Fujian anthracites（Volatile matter:3.56%~4.35%）by carbon dioxide was carried out in the fixed bed reactor of 18 mm inside diameter. The reaction conditions of eliminating both internal and external diffusion effects were determined. Using sodium carbonate as the catalysts, the relationships of coal conversion with reaction time for three low active anthracites (Yong′an Fengshai coal, Yong′an Jiashai coal and Yongding coal ) were explored within the temperature range from 750 ℃ to 907 ℃. Using potassium carbonate and black liquor of paper pulp plant as the catalysts, the relationships of coal conversion with the reaction time for Yongding coal were also studied. The kinetic parameters including the reaction rate constant, the reaction activation energy and the pre-exponential factor were obtained by using the homogeneous model and the shrinking core model. Comparing with the results from the thermogravimetric balance, the reaction rate constant, the reaction activation energy and the pre-exponential factor from the fixed bed are higher than those obtained from the thermogravimetric balance, which could be caused by the higher mass transfer rate of carbon dioxide to the coal surface and higher heating rate in the fixed bed.