| Autor: |
Guoxin Huang, Fei Liu, Aifang Jin, Xiaopeng Qin, Fangming Jin, Qi Zhou, Bing Wu |
| Rok vydání: |
2010 |
| Předmět: |
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| Zdroj: |
AIP Conference Proceedings. |
| ISSN: |
0094-243X |
| DOI: |
10.1063/1.3529341 |
| Popis: |
Nitrate contamination in groundwater has become a major environmental and health problem worldwide. The aim of the present study is to remediate groundwater contaminated by nitrate and develop potential reactive materials to be used in PRBs (Permeable Reactive Barriers). A new approach was proposed for abiotic groundwater remediation by reactive materials of iron chips and granular activated carbon particles. Batch tests were conducted and remediation mechanisms were discussed. The results show that nitrate decreases from 86.31 to 33.79 mg⋅L−1 under the conditions of near neutral pH and reaction time of 1h. The combination of iron chips and activated carbon particles is cost‐effective and suitable for further use as denitrification media in PRBs. Nitrogen species don’t change significantly with the further increase in reaction time (>1 h). The iron‐activated carbon‐water‐nitrate system tends to be steady‐state. Small amounts of ammonium and nitrite (0.033–0.039 and 0.14–3.54 mg⋅L−1, respectively) appear at reaction time from 0 h to 5 h. There is no substantial accumulation of nitrogen products in the system. The removal rate of nitrate only reaches 16.11% by sole iron chips at reaction time of 5 h, while 63.57% by the mixture of iron chips and activated carbon particles. There is significantly synergistic and promotive effect of mixing the two different types of materials on nitrate treatment. Fe/C ratio (1/1.5–1/2.5) doesn’t cause dramatically different residual nitrate concentrations (24.09–26.70 mg⋅L−1). Nitrate can’t be limitlessly decreased with decreasing Fe/C ratio. The concomitant occurrences of chemical reduction, galvanic cell reaction, electrophoretic accumulation, chemical coagulation, and physical adsorption are all responsible for the overall nitrate removal by iron allied with activated carbon. To accurately quantify various nitrogen species, further studies on adsorption mechanisms of nitrite and nitrate are needed. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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