蒿坪河流域石煤矿区河流铝的白色污染及其成因分析

Analysis of White Pollution of River Aluminum in Stone CoalMining Area in Haoping River Basin and Its Causes

矿山酸性水及其伴生的重金属污染是含黄铁矿矿山最主要、综合治理难度最大的污染问题。为了查明蒿坪河流域废弃石煤矿开采河流铝的白色污染及成因问题,2021年以来进行了卫星遥感解译、无固定翼无人机航测、样品采集与分析、主要河流断面水质动态监测等工作。结果表明:(1)研究区河流普遍存在铝的白色污染,其形成可见3种模式:两条沟道不同酸碱度的河水混合后形成白水带;河道河水自然跌水后在河床形成白色污染物;河水自然演化形成酸性水、酸性磺水与酸性白水。(2)河水铝离子污染普遍且超标严重,216件河水中Al离子平均含量为8.6mg/l,样品超标率65.8%,19条河流断面3次河水中Al离子的平均超标率90.48%。(3)河流中铝来自于石煤矿及其围岩中酸性溶解作用长石的结果,废渣堆底部流水是河流铝的主要污染源。(4)河水中铝离子与pH具有显著的负相关关系,河水酸度愈大,河水中铝离子含量愈高;河水中白色无定形胶凝状物形成后,河水中铝离子含量显著降低。河水pH的升高,是河流白色污染物形成的主要因素。河水中铝的白色污染物具有无定形特点,化学组分复杂,是硫酸根、氢氧根及铝构成的复杂化合物。铝的白色无定形胶凝状物具有吸附河水中重金属离子的能力。研究成果可为研究区铝的污染防治提供重要的理论依据。

Acid mine drainage and its associated heavy metal pollution are the most important mine pollution problems in pyrite−bearing mining areas and the most difficult to comprehensively treat.In order to find out the white pollution and causes of aluminum mining rivers from abandoned stone coal mines in the Haoping river basin,satellite remote sensing interpretation,non−fixed−wing UAV aerial survey,sample collection and analysis,and dynamic monitoring of water quality in major river sections have been carried out since 2021.The results show that,①white pollution of aluminum is common in rivers in the study area,and three patterns can be seen:the two channels are mixed with river water with different pH degrees to form white water belts;after the natural fall of the river water,white pollutants are formed on the rock surface of the riverbed;river water naturally evolves to form acidic water,acidic sulfur water,and acidic white water.②Aluminum ion pollution in river water was widespread and seriously exceeded the standard,the average content of Al ions in 216 river waters was 8.6 mg/l,the sample exceeded the standard rate by 65.8%,and the average excess rate of Al ions in the three river waters of 19 river sections was 90.48%.③The aluminum in the river comes from the result of the acid water dissolution of feldspar in the stone coal mine and its surrounding rock,and the flowing water at the bottom of the waste residue pile is the main source of pollution of the river aluminum.④Aluminum ions in river water have a significant negative correlation with pH,and the greater the acidity of river water,the higher the content of aluminum ions in river water;after the formation of white amorphous gels in river water,the content of aluminum ions in river water decreased significantly.The increase in the pH of river water is the main factor in the formation of white pollutants in rivers.The white pollutants of aluminum in river water have amorphous characteristics,complex chemical composition,and are complex compounds composed of sulfate,hydroxide and aluminum.The white amorphous gel of aluminum has the ability to adsorb heavy metal ions in river water.The research results can have important theoretical and practical application value for the pollution prevention and control of aluminum in the research area.