|
| Removal effect of nitrate nitrogen at different concentrations in a simulated riverbed of the Chaobai River |
| Received:June 02, 2021 |
| View Full Text View/Add Comment Download reader |
| KeyWord:reclaimed water;simulated river bed;NO3--N;NO2--N;NH4+-N;removal efficiency |
| Author Name | Affiliation | E-mail | | WANG Xihan | Key Laboratory for Northern Urban Agriculture of Ministry of Agriculture and Rural Affairs, Beijing University of Agriculture, Beijing 102206
Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China | | | WANG Ying | Key Laboratory for Northern Urban Agriculture of Ministry of Agriculture and Rural Affairs, Beijing University of Agriculture, Beijing 102206 | | | LIU Yun | Key Laboratory for Northern Urban Agriculture of Ministry of Agriculture and Rural Affairs, Beijing University of Agriculture, Beijing 102206 | housqly@126.com;杨丽虎，yanglihu@igsnrr.ac.cn | | YANG Lihu | Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China | yanglihu@igsnrr.ac.cn | | LIANG Qiong | Key Laboratory for Northern Urban Agriculture of Ministry of Agriculture and Rural Affairs, Beijing University of Agriculture, Beijing 102206 | | | ZHANG Xixi | Key Laboratory for Northern Urban Agriculture of Ministry of Agriculture and Rural Affairs, Beijing University of Agriculture, Beijing 102206 | | | WANG Junyi | Key Laboratory for Northern Urban Agriculture of Ministry of Agriculture and Rural Affairs, Beijing University of Agriculture, Beijing 102206 | |
|
| Hits: 1238 |
| Download times: 992 |
| Abstract: |
| In recent years, reclaimed water has gradually become the primary water source for urban landscape rivers; however, reclaimed water contains high nitrogen contents, which can cause water and groundwater pollution. The riverbed sediment exhibits an interception and removal effect on NO3--N. In this experiment, a channel device was used to simulate the riverbed of Chaobai River to explore the removal effect of the channel system on NO3--N under three NO3--N concentration levels: low, medium, and high. The results showed that the removal efficiencies of NO3--N were 67.8%, 63.0%, and 55.0% when the concentrations of NO3--N were 5, 10 mg·L-1, and 20 mg·L-1, respectively. The removal effect on NO3--N was improved at 10 cm and 70 cm below the river channel, with a strong correlation between pH and NO3--N concentration in the bottom effluent. The denitrification intensity at 50 cm and 70 cm in sediment was closely related to the concentration of dissolved oxygen. As the temperature decreased, the dissolved oxygen concentration increased, denitrification decreased, and the removal effect of NO3--N worsened. The removal effect of NO3--N was primarily caused by soil leaching, assimilation, denitrification, and dissimilatory reduction. Some nitrogen was retained in the sediment as organic nitrogen formed by assimilation and NH4+-N produced by dissimilatory reduction. The study shows that the riverbed sediment exhibits a purification effect on the reclaimed water channel, which can provide a reference for the safe recharge of reclaimed water to rivers and lakes. |
|
|
|
