摘要
采用热分析法研究了O2/CO2气氛下石灰石及木醋调质石灰石的直接硫化反应过程。结果表明,在实验温度1023～1 173 K,经木醋废液调质的石灰石直接硫化钙转化率显著提高。在1 173 K时,木醋调质石灰石直接硫化反应50 min后钙转化率可达89.55%。木醋调质石灰石的主要成分为水合醋酸钙,调质使石灰石的结构更为疏松,有利于硫化反应的进行。采用缩核模型对反应过程进行了表征,得到石灰石及木醋调质石灰石直接硫化反应速率常数ks和扩散系数Deff的Arrhenius表达式。动力学计算结果表明,相比于石灰石,扩散对木醋调质石灰石直接硫化反应过程的影响较小,说明木醋调质石灰石直接硫化反应性能显著提升的原因为硫化反应扩散阻力的减小。
The direct sulfation reaction of limestone modified by wood vinegar, a kind of waste liquid, was investigated by thermogravimetic analysis method under O2/CO2 atmosphere. The results show that the direct sulfation performance of limestone can be effectively improved by wood vinegar modifying in the experimental temperature range （ 1 023 - 1 173 K）. The phase composition analysis measured by XRD shows that the major composition in the modified limestone is hydration calcium acetate. The structure of limestone modified is much looser than that of original limestone, which is conducive to the direct sulfation reaction. The direct sulfation rate constant （kS ） and product-layer diffusivity （Deef） in Arrhenius expressions were calculated according to the shrinking unreacted core model. The kinetic calculation results show that the diffusion impact of limestone modified by wood vinegar on the direct sulfation process is less than that of original limestone, which means that the limestone modified by wood vinegar has a lower diffusion resistance.
出处
《燃料化学学报》
EI
CAS
CSCD
北大核心
2012年第12期1505-1511,共7页
Journal of Fuel Chemistry and Technology
基金
山东省自然科学基金(ZR2009FQ016)
山东大学自主创新基金(2010TS020)
山东大学研究生自主创新基金(yzc11058)
关键词
O2/CO2
木醋液
调质
石灰石
直接硫化
动力学
缩核模型
02/C02
wood vinegar
modify
limestone
direct sulfation
kinetic
shrinking unreacted coremodel
