摘要
以广东大宝山尾矿库酸性矿山废水(AMD)的水体及其沉积物为研究对象,在槽对坑、铁龙尾矿库的11个采样点进行采样,对水样进行重金属离子含量测定,对沉积物进行物相分析和形貌观测,以探讨铁离子、次生矿物组合与其他重金属元素分布的关系。结果表明:大宝山AMD水体的总铁(TFe)质量浓度介于0.135 3~5.615 4 mg/L,Fe(Ⅲ)/TFe的比值大多高达90%左右,氧化还原电位(Eh)也多数在400~600 mV,属于高度氧化环境。水体Fe(Ⅲ)含量与pH值呈负相关关系,与Eh值呈正相关关系。槽对坑AMD水体Fe(Ⅲ)含量与Mn、Cu、Pb、Zn含量呈正相关,而与其沉积物的Mn、Pb、Zn、Cu含量具有明显的负相关。AMD沉积物中常见含铁次生矿物以铁羟基氧化物和铁羟基硫酸盐矿物为主,如黄钾铁矾、施威特曼石、针铁矿和其他矾类矿物。黄钾铁矾、针绿矾在pH较低(<3.00)、Fe(Ⅲ)含量较高(>3.955 mg/L)时形成;施威特曼石在水体pH相对较高(3.00~4.00)、Fe(Ⅲ)含量相对较低(<1.610 mg/L)时形成;针铁矿和其他矾类次生矿物在所研究的水体pH(2.58~3.72)和Fe(Ⅲ)(0.1580~4.564 3 mg/L)变化范围内均可以形成。不同pH和铁离子条件形成不同的含铁次生矿物组合,对重金属元素的吸附和共沉淀作用,导致重金属元素在水体及其沉积物的分布差异。
Taking the water and its sediments in the acid mine drainage(AMD) at Dabaoshan mine, Guangdong province as the study object, 11 sampling points at Caoduikeng and Tielong tailing ponds were sampled. The concentrations of iron and heavy metal ions in the collected water samples were determined, and the phase analysis and morphological observation of the sediments were carried out to study the effects of iron ion on the formation of secondary minerals and the migration and transformation of heavy metal ions in the AMD. Our study suggests that the total iron(TFe) concentrations in the AMD water were ranged in between 0.135 3~5.6154 mg/L, the ratio of Fe(Ⅲ)/TFe was mostly above 90% and the oxidation-reduction potential(Eh) was mostly in between 400~600 mV, indicating a high oxidation condition. There are negative correlations between Fe(Ⅲ) concentrations and pH values, and positive correlations between Fe(Ⅲ) concentrations and Eh values in waters. There are positive correlations between Fe(Ⅲ) and heavy metal elements such as Mn,Pb,Zn,Cu in waters,and apparent negative relations betweent Fe(Ⅲ) in waters and Mn,Pb,Zn,Cu in the sediments at the AMD in Caoduikeng tailing pond. The common iron-bearing secondary minerals are ferric oxyhydroxide and iron hydroxyl sulfate minerals such as jarosite, schwertmannite, goethite and other alum minerals. The jarosite and coquimbite occurred in low pH values(<3.00) and high Fe(Ⅲ)contents(>3.955 mg/L). Schwertmannite occurred in relatively high pH values(3.00~4.00) and low Fe(Ⅲ)contents(<1.610 mg/L). Goethite and other alum minerals occurred in relatively wide pH values(2.58~3.72)and Fe(Ⅲ)contents(0.158 0~4.564 3 mg/L)in the studied water samples. The various distribution of heavy metal elements in water and its sediment resulted from the absorption and co-precipitation of heavy metals by various iron-bearing secondary minerals formed at different pH values and Fe(Ⅲ)concentrations.
作者
苟习颖
陈炳辉
曹丽娜
李文
张耀
GOU Xiying;CHEN Binghui;CAO Lina;LI Wen;ZHANG Yao(School of Earth Sciences and Engineering,Sun Yat-sen University,Guangzhou 510275,China;Guangdong Provincial Key Laboratory of Geological Processes&Mineral Resources Survey,Guangzhou 510275,China)
出处
《中山大学学报（自然科学版）》
CAS
CSCD
北大核心
2020年第3期12-22,共11页
Acta Scientiarum Naturalium Universitatis Sunyatseni
基金
国家自然科学基金(41373079)
国家重点研发计划项目(2016YFC0600506)。
关键词
酸性矿山废水
铁离子
次生矿物
重金属
大宝山矿
acid mine drainage
iron ion
secondary mineral
heavy metal
Dabaoshan mine
