摘要
将新疆淖毛湖煤(NMH)和内蒙高硫煤(GL)逐级化学提取,考察镉(Cd)在原煤中的赋存形态分布;分别在400−800℃、卧式/立式管式炉对原煤热解,考察赋存形态、热解终温、升温速率和停留时间对Cd释放规律的影响;利用FactSage软件模拟在理想条件下Cd的迁移和转化。结果表明,NMH和GL中Cd的赋存形态分布分别为有机质结合态(46%与37%)、碳酸盐结合态(32%与24%)、二硫化物结合态(12%与1%)、铝硅酸盐结合态(10%与38%)。Cd的赋存形态分布严重影响其挥发行为,有机质结合态易在低温区挥发,而碳酸盐、铝硅酸盐和硫化物结合态需在中高温区挥发;降低热解速率与延长停留时间有助于Cd的释放。FactSage模拟表明,NMH和GL中Cd的气态产物主要有Cd、CdO、Cd(OH)x和CdS,Cd在两种煤中挥发行为的差异主要是由热解温度、赋存形态分布以及煤阶决定,模拟与实验结果吻合较好。
The distribution of cadmium(Cd)occurrence modes in a Naomaohu coal(NMH)and an Inner Mongolia high sulfur coal(GL)was investigated using the sequential chemical extraction method.The influence of the occurrence modes,final pyrolysis temperature,heating rate and residence time on the release behavior of Cd during the pyrolysis of two raw coals at 400-800℃in a horizontal/vertical tubular furnace was examined respectively.The simulation of the migration and transformation of Cd under ideal conditions by FactSage software was carried out.The results show that Cd in NMH and GL is present in an organic matter state by 46%and 37%,a carbonate state by 32%and 24%,a disulfide state by 12%and 1%,and an aluminosilicate state by 10%and 38%,respectively.The distribution of occurrence modes seriously affects the volatilization behavior of Cd,in which the Cd in the organic matter state is easy to volatilize at low temperature,while those in the carbonate,aluminosilicate and sulfide state can volatilize at medium and high temperature;and reducing pyrolysis rate and extending residence time are conducive to the release of Cd.The FactSage simulation shows that Cd,CdO,Cd(OH)x and CdS are the major gaseous products of Cd during the pyrolysis of NMH and GL coal,and the difference of volatilization behavior of Cd in two kinds of coal is mainly determined by pyrolysis temperature,distribution of occurrence modes and coal rank,which are in good agreement with the experimental results.
作者
周玲妹
王晓兵
马晨
刘爽
马茂林
刘姣姣
ZHOU Ling-mei;WANG Xiao-bing;MA Chen;LIU Shuang;MA Mao-lin;LIU Jiao-jiao(School of Chemical&Environmental Engineering,China University of Mining and Technology(Beijing),Beijing 100083,China)
出处
《燃料化学学报》
EI
CAS
CSCD
北大核心
2021年第5期648-655,共8页
Journal of Fuel Chemistry and Technology
基金
国家重点研究发展计划(2016YFB0600304)
国家自然科学基金青年基金(51604280)
中央高校基本科研业务费专项资金(2020YQHH08)
中国矿业大学(北京)越崎青年学者资助计划(2020QN10)资助。
