摘要
对O2/CO2燃烧方式下SO2的脱除机理进行了研究.静态实验和动态实验结果表明这种新型燃烧方式有利于降低SO2的排放,SO2脱除存在均相脱硫和多相脱硫的协同作用;新型燃烧方式下高CO2浓度导致燃烧气氛中化学成分不同于传统的空气气氛,SO2与燃烧气氛中存在的其他组分反应,生成硫的不同形态产物,SO2只是其中的一种产物形态,导致SO2总量排放减少;同时O2/CO2燃烧气氛使燃煤中硫的氧化程度减弱;燃煤中本身所含脱硫剂存在优化的微观结构,该种结构有利于脱硫和对底灰中硫的吸附,也导致SO2的排放量降低;CHEMKIN动力学计算结果进一步表征了以上机理.
O2/CO2 combustion is one of the processes to remove SO2 from pulverized-coal fired bolter, in this paper, SO2 emission and removal in O2/CO2 combustion were investigated in a fixed bed reactor and a drop tube reactor. The results indicated that the amount of SO2 emission was much less than conventional air combustion due to the presence of both homogeneous desulphurization and heterogeneous desulphurization in O2/CO2 combustion. Experimental study also suggested that the change of flue gas composition led to the difference of sulphur oxidation degree and the sulphur in coal could be released in different speciations and SO2 is only one of them. In O2/CO2 atmosphere, the desulphurization agent in coal itself showed different desulphurization behaviour comparing with that in air combustion; the desulphurization agent had an optimized microstructure which was beneficial not only for the improvement of the desulphurization efficiency but also for the adsorption of sulphur in the bottom ash. The kinetics calculation results also verified the above mechanism.
出处
《化工学报》
EI
CAS
CSCD
北大核心
2005年第10期1948-1954,共7页
CIESC Journal
基金
国家重点基础研究发展规划项目(G1999022204-07)
高等学校青年教师教学科研奖励计划(200137)
霍英东教育基金(81048).~~
关键词
二氧化碳
二氧化硫
燃煤
脱硫机理
动力学计算
carbon dioxide
sulfur dioxide
coal
desulphurization mechanism
kinetics calculation
