摘要
采用化学抽提法将义马煤中铅划分为不同的赋存形态,利用程序升温热解反应装置研究了不同形态铅的热稳定性与其迁移转化行为,考察了煤中矿物质对铅释放的影响行为.结果表明,义马煤中约33%的铅以碳酸盐、单硫化物、硫酸盐、磷酸盐与氧化物结合,约29%的铅以硅铝酸盐结合态存在,约27%的铅与二硫化物结合,约8%的铅以有机质结合态存在.有机质结合态的铅热稳定性弱,铝硅酸盐结合态的铅热稳定性强;硅铝酸盐、二硫化物、碳酸盐、单硫化物、硫酸盐、磷酸盐及氧化物矿物质对铅的释放均表现出不同程度的抑制作用;义马煤中不同形态铅的转化主要发生在500℃以上,表现为碳酸盐、单硫化物、硫酸盐、磷酸盐及氧化物结合态铅、二硫化物结合态铅、有机质结合态铅向硅铝酸盐结合态与挥发相的转化.
Occurrence forms of Pb in Yima（YM） coal,their thermal stability and transformation behaviors during coal pyrolysis were investigated.Chemical leaching method was used to characterize the forms of Pb in the raw coal and the chars.It was found that about 33% Pb in YM coal was bound to carbonates,sulfides,sulfates,phosphates and oxides,29% to aluminosilicates,27% to disulfide species,and 8% to organic species.It was also found that the organic bound Pb was the most releasable while the aluminosilicates bound Pb was the least releasable.The effect of minerals of different sort on Pb release was also studied.The result showed that carbonates,sulfides,sulfates,phosphates and oxides,aluminosilicates and disulfides in YM coal could restrain Pb release during coal pyrolysis.The transformation of different forms of Pb mainly occurred at above 500℃ with other forms of Pb transformed to the aluminosilicates form and volatile phase.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2013年第5期2051-2056,共6页
Environmental Science
基金
高等学校博士学科专项科研基金项目(20111401120010)
国家自然科学基金项目(20736001
21203003)
关键词
煤
铅
转化
形态
热解
coal
Pb
transformation
form
pyrolysis
