LEACHATE CHARACTERISTIC AND TREATMENT EFFICIENCY AT KHANH SON LANDFILL, VIETNAM

摘要

The aims of this study were to determine the chemical properties of the leachate and to assess the efficiency of the current leachate treatment process at Khanh Son landfill site, Danang City, Vietnam. The landfill has been operational since 2007 andproduces about 250^00 m3/d and 400-700 m3/d of leachate during the dry and rainy seasons, respectively. Leachate from the Khanh Son landfill is treated before it is discharged into a river; however, there is no reliable data on how effectively the current treatment process is working or on whether the effluent satisfies the National Regulation on Leachate. The research results show that the leachate at the Khanh Son landfill had high concentrations of SS (1500-6600 mg/L), TN (800-1200 mg/L), NH3-N (230-1100 mg/L), and COD (4000-4700 mg/L) and a low ratio of BOD5/COD (0.09-0.19). Sediment tanks showed high efficiencies in removing SS, leading to decreases in TN, COD, and BOD5. Polishing ponds containing vegetation played a crucial role, as they removedsignificant amounts of COD, BODy TN, and color. Anaerobic and anoxic ponds did not perform effectively. Therefore, ceasing operation of the anaerobic and anoxic ponds and using sediment tanks as the first stage in the treatment process are recommended. This study contributes to the development of landfill management by providing recommendations for more effective operation of the leachate treatment system.