建筑垃圾重金属浸出特性及环境污染风险研究进展

Research progress on heavy metal leaching characteristics and environmental pollution risk of construction waste

调研了我国部分地区建筑垃圾中的重金属浓度含量,如Cd、Ni、Pb的浸出浓度范围分别为0.03~0.51,8.12~21.26,40.12~95.10 mg/kg;总结影响建筑垃圾重金属浸出浓度主要因素,如pH值、液固比、粒径大小等,并阐述了建筑垃圾在实际工程中应用途径;对我国典型地区的建筑垃圾重金属进行生态风险评价。潜在生态风险评估结果指出,研究区均为轻度生态风险,其中商丘地区Hg单项潜在生态危险指数73.35,成都和北京地区Cd单项潜在生态危险指数分别为90.91和100.84,是生态风险贡献最大的污染元素;内梅罗综合污染指数评价法与地累积污染指数法结果一致,商丘和西安处于轻度污染水平,北京和成都处于中度污染水平,主要污染因子为Pb、Cd,总体而言建筑垃圾重金属浸出风险与区域特征有较大的相关关系。

The concentration of heavy metals in construction waste in some areas of my country was investigated.For example,the leaching concentrations of Cd,Ni,and Pb ranged from 0.03 to 0.51,8.12 to 21.26,and 40.12 to 95.10 mg/kg respectively;the main factors affecting the leaching concentration of heavy metals in construction waste are summarized,such as pH value,liquid-solid ratio,particle size,etc.The application ways of construction waste in practical projects are described.Finally,ecological risk assessment for heavy metals in construction waste in typical areas of China is carried out.The results of the potential ecological risk assessment point out that the study areas are all mild ecological risks,among which the Hg single potential ecological risk index in Shangqiu area is 73.35,and the Cd single potential ecological risk index in Chengdu and Beijing areas are 90.91 and 100.84,respectively,which are the pollutions with the largest ecological risk contribution.The results of the Nemerow comprehensive pollution index evaluation method and the cumulative pollution index method are consistent,Shangqiu and Xi'an are at a light pollution level,Beijing and Chengdu are at a moderate pollution level,the main pollution factors are Pb,Cd,and construction waste in general.The risk of heavy metal leaching has a greater correlation with regional characteristics.