基于不同能源底物和营养水平的酸性矿山废水产生机制研究  

Study on the mechanisms of acid mine drainage generation based on different energy substrates and nutrient levels

作　　者：王鹤茹 杨琳琳 王蕊[3] 吴怡谦 宋永伟[2,3] WANG Heru;YANG Linlin;WANG Rui;WU Yiqian;SONG Yongwei(Laboratory Centre for Safety and Environment,Zhongnan University of Economics and Law,Wuhan 430073;Department of Environmental Science and Engineering,Zhongnan University of Economics and Law,Wuhan 430073;Institute of Environmental Management and Policy,Zhongnan University of Economics and Law,Wuhan 430073)

机构地区：[1]中南财经政法大学安全与环境实验中心,武汉430073 [2]中南财经政法大学环境科学与工程系,武汉430073 [3]中南财经政法大学环境管理与政策研究所,武汉430073

出　　处：《环境科学学报》2021年第10期4056-4063,共8页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金(No.21906183);湖北省软科学基金资助项目(No.2019ADC152);湖北省教育厅科学研究计划项目(No.B2020447)。

摘　　要：硫化矿物在氧气、水和铁氧化细菌的共同作用下会形成p H值极低、富含可溶性Fe、SO_(4)^(2-)和重金属离子等的酸性矿山废水.本研究选取黄铁矿、磁黄铁矿和黄铜矿作为能源底物,以及0×9K、1/4×9K、1/2×9K、1×9K培养基作为营养水平,在氧化亚铁硫杆菌(Acidithiobacillus ferrooxidans)的参与下,从能源底物和营养水平角度探索不同硫化矿物酸性废水的产生特点和机制.结果表明,3种硫化矿物的生物产酸能力依次为黄铁矿>磁黄铁矿≈黄铜矿.经过38 d的生化反应后,黄铁矿体系的pH值达到1.41,总Fe(TFe)和SO_(4)^(2-)浓度分别达到771.82 mg·L^(-1)和357.25 mg·L^(-1).水体营养水平在黄铁矿的生物产酸过程中起着至关重要的作用.经过16 d的生化反应后,0×9K、1/4×9K、1/2×9K、1×9K培养基处理的终点pH值分别为1.68、1.44、1.30、1.29.根据各营养体系中Fe^(2+)和TFe浓度的变化趋势,以及反应终点收集矿物的X射线衍射(XRD)和扫描电镜(SEM),分析认为充足的营养会提高Acidithiobacillus ferrooxidans的活性或密度,加快Fe^(2+)生物氧化形成Fe^(3+)并通过水解产酸作用合成黄钾铁矾等次生铁矿物,从而导致溶液的p H值更低.本研究所得结果对明晰酸性矿山废水形成规律具有一定的指导意义.Acid mine drainage(AMD),which is characterized by extremely low pH and significant quantities of soluble Fe,SO_(4)^(2-),and heavy metals,is produced from sulfide minerals under the conditions of oxygen,water,and iron-oxidizing bacteria.In this study,pyrite,pyrrhotite,and chalcopyrite were selected as energy substrates and 9K medium with different concentration gradients was chosen as nutrient levels.With the participation of Acidithiobacillus ferrooxidans,the characteristics and formation mechanism of AMD were explored from the perspective of energy substrate and nutrient levels.Results showed that the acid production capacity of the three sulfide minerals was in the following order:pyrite>pyrrhotite≈chalcopyrite.After 38 days of biochemical reaction,the p H was 1.41,the total Fe and total SO_(4)^(2-) concentration of pyrite were 771.82 mg·L^(-1),and 357.25 mg·L^(-1),respectively.In addition,the nutrient level was an important factor in the biological acid-producing capacity of pyrite.After 16 days of biochemical reaction,the final pH values of 0×9K,1/4×9K,1/2×9,and 1×9K medium treatments were 1.68,1.44,1.30,and 1.29,respectively.According to Fe^(2+) and total Fe concentrations trend in nutrient systems,as well as the X-ray diffraction and scanning electron microscopy of minerals collected at the reaction endpoint,it was speculated that adequate nutrition will increase the activity or density of Acidithiobacillus ferrooxidans and accelerate Fe^(2+) biological oxidation and hydrolysis to form jarosite,thus resulting in a low pH of the solution.The results of this study provide scientific significance to clarify the formation rule of AMD.

关 键 词：酸性矿山废水 氧化亚铁硫杆菌 硫化矿物 9K培养基 黄钾铁矾 

分 类 号：X131[环境科学与工程—环境科学]