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研究了利用造纸污泥这一工业固体废弃物作为铅固定剂修复重金属污染土壤的效果和机理.首先通过形态提取试验研究了造纸污泥对土壤中铅形态转化的影响,用X-射线光电子能谱分析了造纸污泥固定铅的机理,最后通过对油菜的盆栽试验评价了造纸污泥修复铅污染土壤的效果.试验发现添加造纸污泥使土壤中铅的可交换态和碳酸盐结合态明显减少,有机结合态和铁锰氧化态显著增加,说明造纸污泥对土壤中铅起到了固定作用.在添加造纸污泥后的土壤中未检出PbCO3和Pb3 (OH)2 (CO3)2,而检测出Pb(C2H3O2)4、Pb(C6H5)4和[Pb3 Cl2(HSCH2C(NH2) HCOO)2],解释了添加污泥使铅碳酸盐结合态的降低及铅有机结合态的增加.铅铁锰氧化态的增加可以用铁元素特征峰向高结合能方向移动解释.添加造纸污泥提高了油菜的干重,减少了铅在油菜中的吸收和积累,降低了铅对油菜的生物有效性和毒性.“,”This study aims to explore the effect and mechanism of reusing paper mill sludge,an industrial solid waste,as a lead stabilizer for remediation of heavy metal contaminated soil.The effect of paper mill sludge on lead forms' transformation was investigated through fractionation test and then X-ray photoelectron spectroscopy analysis was applied to examine the solidification mechanism of paper mill sludge.Finally,by using rape pot experiment,the effect of paper mill sludge on the performance of lead polluted soil remediation was assessed.The results indicate that paper mill sludge has a solidification effect on lead in soil,illustrated by a decrease of the exchangeable and carbonate bound forms of leads;Simultaneously an increase of the organic matter and Fe-Mn oxidation bound forms.After adding the sludge into soil,PbCO3 and Pb3 (OH)2 (CO3)2 were not detected,but Pb (C2H302)4,Pb (C6H5)4 and [Pb3Cl2 (HSCH2C (NH2) HCOO)2] were detected,demonstrating the decrease of carbonate bound forms and the increase of organic matter bound forms,respectively.The increase of Fe-Mn oxidation bound forms can be explained by iron peaks moving to higher binding energy direction.After the sludge application,while the dry weight of rape increases,the lead contents in the rape plants and soil decreases;These results demonstrates the application of paper mill sludge can reduce the bioavailability and toxicity of lead.