石灰石对煤燃烧产生颗粒物及重金属影响实验研究

EXPERIMENTAL RESEARCH OF LIMESTONE EFFECT ON PARTICULATES AND HEAVY METALS EMITTED FROM COAL COMBUSTION

研究0.5 MW循环流化床实验台在混煤稳定燃烧条件下,烟尘颗粒分布规律及炉内投放石灰石对重金属排放的影响。加入石灰石后烟尘浓度从2.98增至5.04 g/Nm3,烟尘颗粒中位径从6.2增至10.1 μm。重金属在颗粒物上的分布规律显示半挥发性元素Pb和cd在小颗粒中的含量随粒径减小而增加,有在亚微米颗粒上富集的趋势。炉内高温燃烧过程中投放石灰石对重金属Hg,Cd,Pb,Ni,Cu有一定的吸附作用。

Particle size distribution and effectiveness of sorbent injection for capture of heavy metals emission were investigated on a pilot scale 0.5 MW CFB test facility using mixed bituminous coal. Particulate matters concentration emitted from coal combustion increases from 2.98 to 5.04 g/Nm3 with the mean diameter increasing from 6.2 to 10.1 μm. Partitioning of the toxic heavy metals show that the concentrations of medium volatilily elements Cd and Pb increase with particle size decreasing and tend to enrich in submicron particles. Limestone injection in high temperature furnace helps to absorb heavy metals including Hg, Cd, Pb, Ni, Cu in coal combustion.