热重法福建无烟煤二氧化碳催化气化的研究

热重法福建无烟煤二氧化碳催化气化的研究

  • 摘要: 采用纸浆黑液为催化剂在一热重分析仪中及常压与750℃~950℃下进行了福建无烟煤二氧化碳催化气化的研究以给出催化剂浓度,即在不同3%、5%、8%、10%钠黑液添加量时对碳转化率的影响。实验表明,在750℃~950℃催化剂浓度8%钠黑液添加量的催化活性比其他浓度更好。在反应控制条件下测定了三种福建高变质无烟煤的碳转化率与气化反应时间的关系。应用均相模型和缩芯模型分别关联了这三种煤的转化率与时间的关系并得出不同温度下的反应速率常数k,进而采用阿累尼乌斯方程 预测了实验所用三种煤的反应活化能Ea 和指前因子A。在适宜催化剂浓度8%钠黑液添加量时,其 Ea=76.18kJ/mol~104.22kJ/mol明显小于无催化剂纯煤气化时的Ea=150.93kJ/mol~185.44kJ/mol数值范围,这明显地表明纸浆黑液是一个廉价和有效的煤气化催化剂。

     

    Abstract: The CO2 gasification of Fuijian anthracite using black liquor (BL) as a catalyst was performed in a thermogravimetry analyzer (TGA) under the temperature ranging from 750℃ to 950℃ at ambient pressure to evaluate the catalytic effect of 3%, 5%, 8%, 10%NaBLLoading on carbon conversion. Better catalytic activity was found with 8%NaBLLoading than those of other concentrations. Under the reaction control conditions the relationships of coal conversion vs reaction time of three kinds of Fuijian highmetamorphous anthracites were measured within temperature range from 750℃ to 950℃. Both homogeneous model (HM) and shrinkingcore model (SCM), were applied to correlate the relations between conversion and time and to determine the reaction rate constants (k) under different temperatures, then the reaction activation energy (Ea) and the preexponential factor (A) of the three anthracites were predicted by using Arrhenius equation k=A·exp(-Ea/RT). The Ea ranged from 76.18kJ/mol to 104.22kJ/mol at 8% NaBL Loading condition was detected, which is less than that from 150.93kJ/mol to 185.44kJ/mol at noncatalyst case, clearly demonstrating that the BL could be the source of inexpensive and effective catalyst for coal gasification.

     

/

返回文章
返回