Coupling biofiltration process and electrocoagulation using magnesium-based anode for the treatment of landfill leachate

JOURNAL OF ENVIRONMENTAL MANAGEMENT

卷:181

Article

Oumar, Dia¹  Patrick, Drogui¹  Gerardo, Buelna²  Rino, Dube²  Ihsen, Ben Salah³ 

[1] Univ Quebec, INRS Eau Terre & Environm, 490 Rue Couronne, Quebec City, PQ G1K 9A9, Canada

[2] CRIQ, 333 Rue Franquet, Quebec City, PQ G19 4C7, Canada

[3] E2Metrix Inc, 3905 Rue Lesage, Sherbrooke, PQ J1L 2Z9, Canada

关键词: Landfill leachate;    Biofiltration;    Electrocoagulation;    Magnesium electrode;    Ammonia nitrogen;    Refractory COD;   

DOI  :  10.1016/j.jenvman.2016.06.067

来源: Elsevier

【 摘 要 】

In this research paper, a combination of biofiltration (BF) and electrocoagulation (EC) processes was used for the treatment of sanitary landfill leachate. Landfill leachate is often characterized by the presence of refractory organic compounds (BOD/COD < 0.13). BF process was used as secondary treatment to remove effectively ammonia nitrogen (N-NH4 removal of 94%), BOD (94% removed), turbidity (95% removed) and phosphorus (more than 98% removed). Subsequently, EC process using magnesium-based anode was used as tertiary treatment. The best performances of COD and color removal from landfill leachate were obtained by applying a current density of 10 mA/cm(2) through 30 min of treatment. The COD removal reached 53%, whereas 85% of color removal was recorded. It has been proved that the alkalinity had a negative effect on COD removal during EC treatment. COD removal efficiencies of 52%, 41% and 27% were recorded in the presence of 1.0, 2.0 and 3.0 g/L of sodium bicarbonate (NaHCO3), respectively. Hydroxide ions produced at the cathode electrode reacted with the bicarbonate ions to form carbonates. The presence of bicarbonates in solution hampered the increase in pH, so that the precipitation of magnesium hydroxides could not take place to effectively remove organic pollutants. (C) 2016 Elsevier Ltd. All rights reserved.

【 授权许可】

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