摘要
采矿废石中的重金属元素会由于废石长时间的露天堆放,受到风化、雨水侵蚀等的作用而释放出来,从而对环境产生一定的危害。以广西某锡钽铌多金属矿区采矿废石为研究对象,对采矿废石样品进行了性质鉴别,并考察了pH、温度和离子强度等环境条件对采矿废石中铅、砷、镉等重金属溶出的影响。结果表明:实验所选取的废石样品为第I类的一般工业固体废物。采矿废石中的铜、铅、镍在pH=4,镉和锌在pH=5,而砷在pH=6的条件下溶出较为明显;重金属元素砷,锌,铜,铅在离子强度为1 ms cm-1时,浸出浓度最大,而镍和镉元素则是在0.1 ms cm-1时出较多;砷,镉和铜在温度为35℃,镍元素在30℃,铅元素在25℃的条件下溶出质量浓度达到最大值,而锌元素的浸出质量浓度受温度的影响较小。
As the solid wastes from mining activity are piled in the open air, the heavy metal of the solid wastes will release after long-term natural weathering, rain, so as to produce certain harm to the environment. In this paper, the mining mullock were sampled from Guangxi tin tantalum and niobium polymetallic mine. The properties of the mining mullock were identified. Furthermore, the effect of environmental conditions, such as pH values, temperature and ionic strength, on heavy metals leaching of mining mulllock were investigated. The results show that the mining mulloek were class I of the general industrial solid waste.And the heavy metal ions were significantly relaeased at the pH value of 4 for copper, lead, nickle, at the pH value of 5 for cadmium and zinc, at the pH value of 6 for arsenic, respectively. In addition, the ion strength has a sigificant influence on heavy metals leaching. Some heavy metals such as arsenic, zinc, copper, lead reach highest leaching concentration at the ion strength of 1 ms·cm-1, wherease some heavy metals such as nickle and cadmium reach highest leaching coneenWation at the ion strength of 0.1 ms·cm-1. Furthermore, the leaching concentration of heavy metal was also influenced by temperature. The leaching concentration of arsenic, cadmium, copper, nickle and lead reaches its highest point at 35℃, 35 ℃, 35 ℃, 30 ℃, 25 ℃, respectively. However, the leaching concentration of zinc was not obviously effected by temperature.
出处
《生态环境学报》
CSCD
北大核心
2013年第3期523-527,共5页
Ecology and Environmental Sciences
基金
环保部公益性行业科研专项项目(201009037)
关键词
采矿废石
重金属元素
溶出特性
mining mullock
heavy metal
leaching characteristics
