Steam gasification of kraft black liquor char was performed at 8601 in a tube furnace with direct causticization using anatase titanium dioxide and recycled sodium tri-titanate. The organic carbon in the black liquor char could be completely gasified within 6 min, approximately equal to the complete conversion time of sodium carbonate in black liquor char to sodium penta-titanate at these conditions, and the generated dry gas had a high heating value of nearly 10 MJ/m3. The main component of solid product was sodium penta-titanate, and the sodium tri-titanate recycled from hydrolysis of sodium penta-titanate had satisfactory reactivity compared to fresh titanium dioxide. No agglomeration of solid product was observed through the process of reactions. About 20% of total sulfur in black liquor retained in the gasified residual solid in the form of non-reduced state.%采用锐钛矿型二氧化钛对两种硫酸盐黑液半焦在860℃的温度下进行了直接苛化与水蒸气气化实验.结果表明:黑液半焦中的有机碳可在6 min内气化完毕,直接苛化反应也可在此时间内完成；气化所得气体的干基高位热值约10 MJ/m3；气化与直接苛化所得固体产物熔点高于900℃且粉末状态良好,主要成分为五钛酸钠,该产物水解后生成氢氧化钠和不易继续水解的三钛酸钠；回收的三钛酸钠继续用于直接苛化实验时,固体产物没有发生结块现象,可以循环利用；约占黑液总硫20％的硫以非还原态留存于气化残余固体中.
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