修复植物热解过程中重金属元素迁移行为研究

在管式炉反应器中研究了重金属土壤修复植物长香谷稻秆中Cd、Pb、Mn、Cu和Zn在不同温度、停留时间和反应气氛下的迁移行为,结果表明：在低于元素挥发的温度热解时,固体残渣中重金属元素的富集倍数随温度的升高而增加;在元素挥发的温度热解时,该元素在固体残渣中的富集倍数随着停留时间的延长而减少;800℃以上CO2气氛比N2气氛更有利于Mn、Cu和Zn在热解残渣中富集。选择合适的热解条件能够达到将原料减容减重并富集其中特定重金属元素的目的。

Study on transfer behavior of heavy metals during pyrolysis of phytoremediating plant

Transfer behavior of Cd,Pb,Mn,Cu and Zn during phytoremediating plant pyrolysis was studied in this paper.Pyrolysis experiments were carried out in a tube furnace reactor.The effects of temperature,residence time and atmosphere on the enrichment behavior of heavy metals in solid residues were investigated.The results showed that the enrichment factor of the element increased with increasing temperature when pyrolysis temperature was lower than the heavy metal releasing temperature,However,the en-richment factor of the element decreased with increasing residence time when pyrolysis temperature reached the heavy metal releas-ing temperature.Besides,above 800 ℃,the enrichment factor of Mn,Cu and Zn was higher in CO2 atmosphere than that in N2 at-omsphere.The results implies that pyrolysis is an important option for volume reduction of phytoremediating plants.Meanwhile,the heavy metals can be enriched in the residues（pyrolysis chars）,and that might be further treated or utilized.