|
| Migration characteristics of salts and heavy metals with rainwater leaching in the co-ecological disposal area consisting of red and dehydrated mineral mud |
| Received:September 23, 2022 |
| View Full Text View/Add Comment Download reader |
| KeyWord:red mud;dehydrated mineral mud;rainwater leaching;ion transport;heavy metal |
| Author Name | Affiliation | E-mail | | JIANG Xusheng | Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin 541004, China | | | CHENG Guanwen | Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin 541004, China | | | LIU Jie | Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin 541004, China
Technical Innovation Center of Mine Geological Environmental Restoration Engineering in Southern Karst Area, Ministry of Natural Resources, Nanning 530022, China | liujie@glut.edu.cn | | YU Guo | Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin 541004, China
Technical Innovation Center of Mine Geological Environmental Restoration Engineering in Southern Karst Area, Ministry of Natural Resources, Nanning 530022, China | | | CHEN Shiqi | Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin 541004, China | | | HAN Qingkun | Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin 541004, China | | | WANG Luyang | Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin 541004, China | |
|
| Hits: 782 |
| Download times: 870 |
| Abstract: |
| This study explored the migration characteristics of salt and heavy metals leached by rain in the co-ecological disposal area consisting of red and dehydrated mineral mud in the Pingguo bauxite mining area of southern Guangxi. A field experiment was carried out by burying leaching trays at different depths of soil in the ecological disposal area and surrounding soil to monitor the content of heavy metals and salts in the monthly leaching solution. The matrix samples at different depths were subsequently collected, and the contents of the heavy metals and salt ions were determined. From May to October, the average leaching amount of Na salt in the red mine mud base （made by turning and mixing red mud and dehydrated mineral mud at a dry weight ratio of 1∶3）reached 51.2 mg·m-2·month-1, whilst the leaching volume of Na in August reached 108 mg·m-2·month-1. After eight months of ecological treatment, the pH of the red mine mud decreased from 9.06 to 8.70, the electrical conductivity（EC）decreased by 80.0%, and the Na salt content had decreased by 70.4%. The Na salt in the red mine mud base migrated to the surrounding soil along with the rain leaching, significantly increasing（P<0.05）the pH and EC values of the surrounding 1.5 m of soil. However, the migration influence range was within 3 m. For ecological disposal, the total loss of Cd, Cr, and As in the red mine mud base layer with rainwater leaching was less than 0.22 mg·m-2·month-1, whilst the heavy metal contents of Cd and As in the red mine mud and surrounding soil showed no significant changes. Therefore, the application of a red mine mud base for ecological disposal in the mining area was beneficial for the reduction of the high salinity in the red mine mud base. In contrast, the migration of sodium salt in the red mine mud had a limited impact on the salinity of the surrounding soil. Furthermore, the risk of heavy metal pollution from ecological disposal in mining areas could be controlled. |
|
|
|
