Study On The Inhibition Of Acid Mine Drainage And Heavy Metal Release In Copper Mine Dump

Much acid mine drainage released during the metal sulfide mining process,accompanying by high concentrations of heavy metals.The ecological restoration of metal sulfide mining wasteland is always the difficulty of metal mine ecological restoration.The most critical issue in controlling the environmental risks of metal sulfide mines is the suppression and hindrance of the production of acid mine drainage.This study takes copper oxide ore dump soil as the research object,and through the column leaching experiments to study on the inhibition of the release of acid and heavy metals from 4 kinds of ecological restoration materials,that were bentonite,organic fertilizer,phosphate fertilizer and arbuscular mycorrhizal.I hope that the conclusions of this study can provide technical support and scientific basis for dumping acidic metal sulfide mine ecological restoration.The main conclusions of this study include:(1)In the whole column leaching experiment,the soil produce acid faster at the beginning and slower then,and lower soil sulfide producing lower acid than the upper soil because of lack of oxygen;(2)heavy metals were released while the sulfide oxidation to produce acid,and the dissolution law of Zn is slower at the pre-leaching,and get faster at the late-leaching;the released of Cu mainly concentrated in the pre-leaching period,then get slower after that;while Pb leaching occurs mainly in the first month,but almost no released then;(3)adding phosphate fertilizer,organic fertilizer,bentonite and arbuscular mycorrhizal all can inhibit the release of acid and heavy metal from mine waste soil,and bentonite has the best effect of acid suppression;inhibition of the release of heavy metals had a better effect of bentonite and arbuscular mycorrhizal,than phosphate fertilizer and organic fertilizer;(4)organic fertilizer has the best effect on the passivation of three heavy metals;the heavy metals also can be passivated by the other three ecological restoration materials,but the passivation effect is not obvious;(5)bentonite,phosphate fertilizer and arbuscular mycorrhizal can reduce the absorption of heavy metals of bermudagrass,and inhibition of the release of heavy metals had a better effect of bentonite and phosphate fertilizer than arbuscular mycorrhizal;and organic fertilizer just has a little effect on reducing the absorb of Pb,and no obvious inhibitory effect on the other two kinds of heavy metals.