| Abstract:The open-pit mining of non-ferrous metal mines has caused environmental problems such as high and steep slopes and soil acidification, which is the main technical difficulty of ecological restoration. In this study, taking the acid surface mining slopes of the Zijinshan Gold-Copper Mine in Fujian as the study object, on the basis of environmental background investigation and soil sample analysis, the control method of slope acidification is studied. The mining area includes all kinds of slopes composed of bare rock on the end boundary, rock and soil mixture in the dump and residue produced in the mineral processing process. Two kinds of oxygen barrier covering acidification control methods have been developed, one was invented with 35 % ~ 45 % sandy soil, 5 % ~ 10 % calcium oxide, 10 % ~ 20 % cement, 150 g ~ 200 g potassium polyacrylate, 20 kg ~ 60 kg organic chelating agent for 1 m2 of meterial; the other was prepared by 80 % ~ 90 % neutralizing slag, 5 % ~ 10 % microbial fertilizer and organic fertilizer 1 % ~ 5 % for 1 m2 of meterial. The results of the engineering practice performance showed that the pH value of the surface soil increased from 2.78 ~ 5.05 to 8.21 ~ 8.56. And the average content of S decreased by 70%, soil acidification was effectively controlled, and the three-dimensional plant community was gradually restored. This study provided the best industrial practice demonstration for the ecological restoration and treatment of end mining environment interface in non-ferrous metal mines. |
