Study On Characteristics, Mechanism Experiments And Preventions Of Acid Mine Drainage

Based on consulting plenty of documents at home and abroad,analyzing the geologic formative background(formation,hydrogeologic condition,sulfur content characteristics of coal)on the acid mine drainage(AMD)in Sitai mine,investigating hydrology characteristics of acid water in the mining area,and carrying out the simulated experimental research.Its content includes:(1)pH values of acid mine drainage in the mine are between 2.99 and 3.7,hydrogeologic types can be descript as Ca-Mg-Na-SO₄,which has low pH values,high sulfate iron,high conductivity,high hardness and high concentration of total dissolved substance.The water samples are classified by principal component and cluster analysis.After treatment of AMD,pH values of water quality are between 7.08 and 7.95,hydrogeologic types are characterized by Ca-Mg-SO₄,which has high calcium ion and lower ferric ion;(2)in order to analyze acid-producing mechanism,using the batch reactor to carry out the oxidized-dissolution experiment in different conditions,observing the changed timing pH,Eh,EC values,selecting the concentration of sulfate ions as Reaction Progress Variable,then calculating the oxidized reaction rates of pyrite,the experiment indicates that raising temperature can accelerate the oxidized reaction rates of pyrite,meanwhile it can improve the dissolution of pyrite.When the reaction is over,total Fe and ferrous ion are measured,then calculating solubility and its rate of iron element,and obtaining the result that the concentrations of total Fe are less than the ferric ions before the reactions;(3)eventually,focusing on the practical condition of AMD in Sitai mine and binding the research methods at home and aboard to put forward preventive measures, as to provide the advices for the research on AMD in similar mine in our country.