建筑垃圾中镉和砷的释放特征研究  

Characterization of Cd and As Released from Construction and Demolition Wastes Recycled in Road Construction

作　　者：陈宇云[1,2] 贾瑞[2] 杨胜科[2] 赵晓红[2] 王周峰[2] 王文科[2] 杨银科[2] 

机构地区：[1]旱区地下水文与生态效应教育部重点实验室,陕西西安710054 [2]长安大学环境工程与科学学院,陕西西安710054

出　　处：《环境科学与技术》2016年第9期50-55,111,共7页Environmental Science & Technology

基　　金：陕西省交通建设集团公司2011年度交通科技项目(2013610102000423);陕西省自然科学基金(2014JM5204);中央高校基本科研业务费专项资金资助项目(2013G1502035)

摘　　要：为了探究拟用于公路工程的建筑垃圾是否会对环境产生危害,对公路沿线建筑垃圾分类加工厂的130多个点进行取样分析,检测8种重金属（Cr、Cd、As、Ni、Cu、Zn、Pb、Mn）含量,检测结果与我国土壤环境质量Ⅲ类标准限值比较,发现重金属镉（Cd）和砷（As）有超标现象,其余重金属均未超标。由此可知,Cd和As是主要污染物。通过对建筑垃圾样品进行浸泡振荡模拟试验并使用电感耦合等离子体质谱法（ICP-MS）,测定不同液固比、不同温度、不同p H值条件下Cd和As的含量,分析建筑垃圾中Cd和As的释放特性及规律。结果表明,建筑垃圾的液固比（0.4-10）越高,Cd和As的释放量越大,释放浓度越低;p H值（4-7）越高,Cd和As的释放浓度越低;随着温度（25-45℃）变化,Cd的释放规律与As明显不同。Cd和As最高释放浓度相对于我国地表水环境质量标准和地下水质量标准均处于Ⅰ、Ⅱ或Ⅲ类标准,也低于欧盟相关标准的无危害值,表明建筑垃圾中污染物Cd和As的释放量均处于较低水平,用于公路建设对环境是无危害的。Construction and demolition wastes generated in a great amount can be recycled in road building, for this purpose sampling and analyzing of the wastes were conducted with more than 130 samples of debris to detect content of eight heavy metals such as Cr, Cd, As, Ni, Cu, Zn, Pb and Mn. The results showed that content of Cd and As exceeded standard in a few samples compared with Class Ⅲof the National Soil Environmental Quality Standard, indicating Cd and As were the major contaminants. The further experimental study was the immersion oscillation simulation test which involved studying release characterization of Cd and As at different liquid to solid ratio, pH value and temperature using ICP-MS. The findings of the study presented that the lower liquid to solid ratio （ranging 0.4 to 10）, the more release and the lower concentration of the contaminants （Cd and As）, while the lower pH value （ranging 4 to7）, the higher release concentration of the contaminants; and release behavior of Cd and As differed a lot with the change of temperature （ranging 25-45 ℃）. As to the concentration of released contaminants （Cd and As） in the leachants, the study presented there was non-hazardous risk in recycling construction and demolition wastes in this regard when comparing with the National Surface Water Environment Quality Standard, National Groundwater Quality Standard, as well as with the relevant EU standard.

关 键 词：建筑垃圾 Cd和As 释放特征 风险分析 

分 类 号：X705[环境科学与工程—环境工程]