摘要
为了预测雨水作用下港口矿石堆场潜在的重金属污染风险,以港口矿石堆场内铜精矿和铅精矿为研究对象,通过动态淋溶试验和重金属形态分析研究了矿石在雨水作用下重金属的释放规律及其与重金属形态特征的关系。结果表明:铜精矿中的Zn和Cd释放规律基本一致,累积释放量随时间变化的曲线可分为快速释放(1 d内)和慢速释放(1 d后)两个阶段,其中,快速释放阶段Zn和Cd的释放量分别占淋溶周期内全部释放量的98.29%和98.02%;铅精矿中Zn和Pb的累积释放量则随时间呈线性增长。矿石中重金属形态的分析结果进一步表明,铜精矿中Zn和Cd的水溶态所占比例大。水溶态重金属的迁移性强,可在短时间内快速释放,因而在雨水作用下环境污染风险较大。经比较,铜精矿中Zn和Cd的水溶态质量比与动态淋溶快速释放阶段的释放量基本吻合。铅精矿中的Zn和Pb的水溶态所占比例小,淋溶释放量也小,尤其是Pb与SO2-4形成沉淀,环境污染风险较低。
In this paper, we would like to bring forward the results of our investigation for predicting the potential risk from the rain leach- ing with heavy metal ingredients due to the rain leaching in the copper ore and lead ore in the harbor stockyard. The results of our investiga- tion have shown that the leaching behaviors of Zn and Cd in the cop- per ore prove to be similar. The cumulative amounts of Zn and Cd that are released in the leaching period could be divided into two stages, namely, a rapid leaching stage （within 1 d） and a slow leaching stage （after 1 d） . The amounts of Zn and Cd released in the rapid leaching stage turn to account for 98.29 % and 98.02 % of the total amounts released in the said leaching period. The cumulative amounts of Zn and Pb released in the lead ore prove to increase lin- early with the time passing on. The speciation results of heavy metals in the ore further reveal that the water soluble fraction of Zn and Cd in the copper ore both takes quite a large proportion. In addition, the water soluble fraction of heavy metals has a high mobility, which is likely to be released in a short time. Therefore, whenever it rains, the water soluble fraction of heavy metals would leach in a short time, leading to a high environment risk. However, it is comparable for the amounts of water soluble fraction of Zn and Cd in the copper ore to those released in the rapid leaching stage. The proportions of water soluble fraction of Zn and Pb in the lead ore as well as their cumula- tive amounts released in the leaching period were small. In particu- lar, Pb and SO42- can form precipitate which has a low mobility. Thus, leaching of Zn and Pb in the lead ore can merely lead to a mi- nor environment risk.
出处
《安全与环境学报》
CAS
CSCD
北大核心
2013年第5期99-102,共4页
Journal of Safety and Environment
关键词
环境学
港口矿石堆场
铜精矿
铅精矿
重金属形态
雨水淋溶
environmentalology
port stockyard
copper ore
leadore
speciation of heavy metals
rain leaching
