不同来源重金属元素在混凝土中的浸出性研究

Study on Leachability of Heavy Metal Elements in Different Sources in Concrete

研究了不同来源重金属元素在混凝土中的浸出性,从胶凝材料、骨料和外加重金属元素三方面阐述重金属元素的浸出性。结果表明,纯水泥、水泥与粉煤灰质量比为7∶3、水泥与矿粉量比为7∶3三种胶凝体系中的重金属浸出率低,其中,纯水泥浆体中检测不到重金属离子的浸出;所选四个地区的天然粗骨料和六个地区的天然细骨料中的重金属含量和重金属浸出性各有差异,其中Pb和Zn相对含量及浸出率较高;而骨料中重金属的浸出率极低,Zn的相对浸出率较高;水泥净浆中外掺六种可溶性重金属盐或重金属氧化物表现出不同的重金属浸出性,外掺重金属氧化物,净浆的重金属浸出率较低,而外掺可溶性重金属盐,水泥净浆的重金属浸出率相对较高。

The leachability of heavy metal elements in different sources of concrete including cementitious materials, aggregates and adding soluble heavy metal salts or heavy metal oxides was investigated. The results showed that the pastes of pure cement, 70% cement ＋ 30% fly ash and 70% cement ＋ 30% slag have low heavy metal elements leachability and pure cement pastes have no heavy metals extraction content; coarse aggregates obtained from four districts and fine aggregate obtained from six districts have different heavy metal elements content and different leachability; heavy metals leachability of cement pastes was increased when adding soluble heavy metal salts into cement pastes compared with adding heavy metal oxides.