煤气化过程中痕量元素迁移规律与气化温度的关系

在一台常压流化床气化炉上，维持流化风量7Nm3/h、蒸汽量1.32kg/h、给煤量3.17kg/h、静止床层高度400mm等气化参数不变，详细研究了痕量元素迁移规律与气化温度之间的关系。结果表明：气化温度对痕量元素迁移规律的影响比较复杂，并非气化温度的升高都能促进所有痕量元素挥发，元素及其化合物的熔、沸点对元素挥发影响很大，但不是唯一决定因素。痕量元素在高、低温焦中受气化温度影响变化趋势相同，即随着气化温度的升高，As、Cd、Co、Cr、Cu、Mg、Ni、Pb、Se的相对富集系数增加，Zn的相对富集系数减小，Mn、Hg、V、Sr的相对富集系数变化很小。 相对于高温焦，低温焦中As、Cd、Co、Cr、Cu、Hg、Pb、Se、Zn具有较高的相对富集系数。底渣中大部分痕量元素（As、Cd、Co、Cu、Mg、Ni、Pb、Se）的相对富集系数随着气化温度的升高而减小。

The Relationship Between Occurrence of Trace Elements and Gasification Temperature

The relationship between occurrence of trace elements and gasification temperature in an atmospheric fluidized bed gasifier has been studied in detail, with airflow rate of 7Nm3/h, steam feed rate of 1.32kg/h, coal feed rate of 3.17kg/h and static bed height of 400mm. The results may be summarized as follows: The gasification temperature's influence on the occurrence of trace elements is complicated. Higher gasification temperature can't always increase the volatilization of trace elements. The melting and boiling points of elements and their compounds greatly influence the occurrence of trace elements, but are not the only factor. There are other factors to influence the occurrence of trace elements. The higher gasification temperature, the higher the relative enrichments (RRE) of As, Cd, Co, Cr, Cu, Mg, Ni, Pb, Se and the lower of Zn in the high temperature coke and the low temperature coke. The RRE of Mn, Hg, V, Sr are not affected by gasification temperature in the high temperature coke and the low temperature coke. The RRE of As, Cd, Co, Cr, Cu, Hg, Pb, Se, Zn in the low temperature coke are larger than those in the high temperature coke. The REs of As, Cd, Co, Cu, Mg, Ni, Pb, Se in the bottom ash are decreased with the increase of gasification temperature.