| Coal gangue is the solid waste, which produced from process of coal mining and coal washing. Acid mine drainage is a kind of pollution source produced from process of coal mining.In this paper, spontaneous combustion coal gangue was used as raw materials, which produced in Qinghemen, Fuxin. The modification methods and removal of Fe2+ and Mn2+ from acid mine drainage was studied by modified spontaneous combustion coal gangue, and the removal mechanism of Fe2+ and Mn2+ was discussed.By the single factor experiment, the results indicated that optimum reaction condition of removal effect of Fe2+ and Mn2+ by spontaneous combustion coal gangue were:particle size 80-120 mesh, dosing quantity 4g/50ml, pH value 5, reaction time 150min. Spontaneous combustion coal gangue was chemical modied, and through the comparison of the removal effect of Fe2+ and Mn2+ showed that the modification effects of NaOH> the modification effects of NaCl＞the modification effects HC1. NaOH as the modifier, concentration 3 mol/L, liquid-solid ratio 2:1, soaking time 8 h. Under these conditions, removal rate of Fe2+ and Mn2+ is respectively 92.53% and 87.54%. Adsorption process conforms to the secondary dynamics equation and the Freundlich adsorption model.Experimental study on dynamic adsorption showed that compare with unmodified spontaneous combustion coal gangue and NaOH modified spontaneous combustion coal gangue, the spontaneous combustion coal gangue combined with microbe had good removal efficiency on Fe2+, Mn2+, SO42- and COD, which had strong sustainable capacity. The highest removal rate achieved respectively 99.85%,70.72%86.05% and 74.91%.The X-ray diffraction （XRD） and scanning electron microscopy （SEM） was used to characterize the test results. The results showed that the adsorption process of pollutions by coal gangue was mainly surface coordination reaction, ion exchange reflect, redox reaction and chemical precipitation reaction. |
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