摘要
在固定床反应装置上考察了商业载硫活性炭脱除天然气中气态Hg0的吸附性能、影响因素、再生方法以及吸附动力学,同时结合BET,FTIR,XRD等表征手段提出载硫活性炭脱汞机理.结果表明,空速对脱汞效率限制作用有限,空速从12000h-1提高至48000h-1,脱除率变化范围在7%以内.增加汞浓度在初始阶段可以提高其脱汞率,增加单位质量活性炭对汞的吸附量,提高温度会增加吸附体系内的活化分子,提高脱汞率,温度在80℃时效果最优,但是温度过高则会产生负面效应.不同阶段的动力学拟合结果表明化学吸附是整个吸附过程的控制步骤.热脱附实验表明载硫活性炭的脱汞温度是在300-450℃,再生后对汞的吸附能力减弱,其原因可归为再生过程中碳硫键的损失和活性炭二次碳化时表面的烧蚀.
The adsorption performance, influence factors, regeneration method and the adsorption dynamics of the gaseous Hg0 in natural gas removed by commercial sulfur-loaded activated carbon were studied on fixed reacting device. Meanwhile, the removal mercury mechanism of S-loaded activated carbon was put forward by applying characterization methods, including BET, FTIR, XRD and etc. The result showed that the restriction effect of airspeed on removal mercury efficiency was limited. In the initial stage, removal mercury rate and adsorption capacity of element mercury can be raised by increasing mercury concentration. As temperature gets higher, the activated molecule in the system get higher and the removal mercury rate will be promoted. The best effect appeared at 80℃. But when temperature was higher than 80℃, negative effects arose. Dynamic fitting in different stages showed that chemical adsorption was the controlling step of the whole process. Besides, the thermal desorption experiment showed that the removal mercury temperature of s-loaded activated carbon ranged from 300℃ to 450℃, and the absorption capacity of regenerate activated carbon was weakened because of the loss of c-s bond in the regeneration and the surface ablation of activated carbon in the process of twicecarbonization.
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2016年第2期382-389,共8页
China Environmental Science
基金
教育部科学技术重点项目(211157)
四川省杰出青年基金(13QNJJ0110)
四川省教育厅创新团队项目(14TD0020)
成都市科技局科技惠民技术研发项目(2015-HM01-00127-SF)
成都信息工程大学校青年学术带头人科研基金(J201513)
关键词
载硫活性炭
天然气
影响因素
动力学
脱附
s-loaded activated carbon
natural gas
absorption mechanism
dynamics
desorption