摘要
利用热重-红外联用技术(TG-FTIR)研究了芒草与褐煤共热解,并与玉米秸秆和褐煤共热解进行了比较。结果表明:共热解过程分为3个阶段,即预热干燥阶段、挥发分析出阶段和炭化阶段;由动力学分析及加权分析可知,芒草或玉米秸秆与褐煤共热解均具有协同作用,均可促进褐煤的热解,芒草与褐煤共热解反应更易发生;共热解协同作用随着生物质掺混比(质量比)的增加而增强,玉米秸秆掺混比变化对协同作用的影响更为明显;由红外分析可知,芒草与褐煤共热解可以降低褐煤的热解温度,促进褐煤的热解反应;芒草与褐煤共热解过程中CH_4,CO_2和CO的析出规律,在低温段时与芒草热解过程中三种气体的析出规律相似,在高温段时是芒草和褐煤综合作用的结果;当芒草与褐煤的掺混比为1∶2时,掺混芒草能有效优化热解气的组分,提高CH_4和CO的体积分数。玉米秸秆与褐煤共热解过程中CH_4,CO_2和CO的析出规律与玉米秸秆热解过程中三种气体的析出规律相似,几乎不受褐煤影响,其受掺混比的影响较小。
Co-pyrolysis characteristics of miscanthus and lignite were studied using TG-FTIR,which was compared with that of corn stalks and lignite.The results show that the co-pyrolysis process can be divided into three stages-water evaporation stage,mevolatilization stage and carbonization stage.Kinetic analysis and weighted analysis show that the co-pyrolysis of miscanthus or corn stalks and lignite has synergistic effect,which will promote the pyrolysis of lignite.As a result,the co-pyrolytic reaction of miscanthus and lignite is likelier to occur.The synergistic effect of the co-pyrolysis for biomass and lignite is enhanced when the mixing ratio(mass fraction)of biomass increases.And the effect of the mixing ratio of corn stalks on synergistic effect is more obvious.Infrared analysis shows that the co-pyrolysis of miscanthus and lignite is able to reduce the pyrolysis temperature of lignite so as to promote the pyrolysis reaction of lignite.At low-temperature stage,the release principle of CH 4,CO,and CO 2 from the mixture of miscanthus and lignite is similar to that of miscanthus.At high-temperature stage,the release behavior of CH 4,CO,and CO 2 results from the combined action of miscanthus and lignite.When the mixing ratio of miscanthus and lignite is 1∶2,miscanthus can effectively optimize the composition of the pyrolysis gas and increase the volume fraction of CH 4 and CO.The release principle of CH 4,CO,and CO 2 from the mixture of corn stalks and lignite is similar to that of corn stalks,and it is almost unaffected by lignite.The blending ratio has little influence on it.This phenomenon indicates that there is a synergistic effect in the co-pyrolysis process of corn stalks and lignite.
作者
焦豪
田红
胡章茂
姚灿
吴楠
郭深
JIAO Hao;TIAN Hong;HU Zhangmao;YAO Can;WU Nan;GUO Shen(School of Energy and Power Engineering,Changsha University of Science and Technology, 410114 Changsha,China;School of Energy and Environment,Southeast University, 210096 Nanjing,China;School of Energy and Power Engineering,Dalian University of Technology,116024 Dalian,China)
出处
《煤炭转化》
CAS
CSCD
北大核心
2019年第1期22-30,共9页
Coal Conversion
基金
国家自然科学青年基金资助项目(51706022)
湖南省自然科学青年基金资助项目(2018JJ3545)
湖南省教育厅优秀青年项目(16B001)
关键词
芒草
褐煤
共热解
协同作用
热解动力学
热解产物
miscanthus
lignite
co-pyrolysis
synergistic effect
pyrolysis kinetics
pyrolysis products
