The experiments on the catalytic gasification of pulverized Fujian Longyan anthracite by using black liquor as the catalyst and oxygen enriched mixing gas (oxygen enriched air/steam) as the gasification medium were carried out in a bench-scale fluidized bed reactor. The effects of catalyst (black liquor) addtive on the carbon conversion, gas yield, gas composition and calorific value were evaluated under different enriched oxygen concentrations. The results show that the dual effects of the black liquor catalyst and the enriching of oxygen in feed air can greatly improve the carbon conversion and the effective composition of gas products. However, the catalytic gasification of coal by alkali in black liquor and the calcination (vitrification) reactions of SiO2 and Al2O3 in coal ash with alkali in black liquor coexist in the same process, and these reactions exhibit a certain competition at 870℃. In addition, a series reactions between carbon and gas medium at high temperature may be enhanced differently by alkali in black liquor. Based on the experimental results and above analysis the optimum operation condition for the black liquor catalyzed gasification of Fujian Longyan anthracite in enriched oxygen medium is proposed. The oxygen concentration of 40% and the ratio of steam to oxygen enriched air ranging from 1.4kg/m3 to 2.0kg/m3 will have the best results，such as 94% of carbon conversion, 3.62m3/kg of gas yield and 7.33MJ/m3 of calorific value of gas products.
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