修复植物热解过程中重金属迁移转化特性的研究进展

Research progress of heavy metal transformation and migration behavior during pyrolysis of phytoremediating plants

植物修复技术能够有效治理土壤重金属污染,而富集重金属后的修复植物须妥当处理才能避免二次污染。修复植物得到有效处理的理想状况是通过热解法将重金属以稳定形态富集到热解炭中,避免重金属迁移到热解气或热解油中。文章围绕修复植物的热解处理,综述了原料性质、热解温度、热解时间、升温速率、反应气氛以及添加剂这6个因素对重金属迁移转化特性的影响,并提出了今后该领域的研究方向,为无害化热解处理修复植物以及固相产物的增值利用提供了参考。

Phytoremediation technology can effectively remediate heavy metal contaminated soil,and the resulted heavy metal accumulated phytoremediating plants should be properly disposed to avoid secondary pollution. A proper pyrolysis condition should stably immobilize heavy metals in biochar and avoid the migration of heavy metals from plants into syngas and bio-oil for disposing of phytoremediation plants. This review focused on the studies of the pyrolysis of phytoremediating plants and summarized the influence of six factors on heavy metal transformation and migration behavior, including raw material properties, pyrolysis temperature, retention time, heating rate,reaction atmosphere and additives. Future research areas were also suggested for improving pyrolysis as a harmless disposal method for phytoremediating plants and value-added utilization of solid product.