| Title |
Nitrogen Removal from Landfill Leachate by SBR |
| Authors |
최의소 ; 이경수 ( Eui So Choi ; Kyeong Su Lee ) |
| Abstract |
Nitrogen removal from sanitary landfill leachate representing average COD of 3000㎎/ℓ and TKN of 1200㎎/ℓ intensively studied with SBR operated with 5d HRT(30d SRT) with 24hr cycle time at 20℃. Addition of phosphorus as nutrient was necessary, but pretreatments like ammonium stripping, and electrolysis did not improve the overall nitrogen removal since the elevated pH showed increased inhibition to nitrifiers. NO₂N accumulation was typical phenomenon throughout the operating periods and this inhibited the conversion to NO₂N. However, nitrogen removal efficiencies were varied with COD/TKN ratio; higher nitrogen removal with higher ratio and lower removal with lower ratio. COD/TKN$gt; 4.6 exhibited more than 93% nitrogen removal efficiencies. Addition of acetate as external carbon source could improve nitrogen removal efficiencies. Acetate requirements as COD were respectively 1.49㎎ COD/㎎ NO₂N, and 2.01㎎ COD/㎎ NO₄ N. The remained NO₂N in effluent increased COD, and a complete removal of NO₂N would reduce the COD concentrations in the effluent. Kinetic evaluation would suggest the denitrification from NO₂N could reduce the aeration and anoxic times to 30% and external carbon source to 26% in comparison to those from NO₃N. |