Treatment of landfill leachate using single-stage anoxic moving bed biofilm reactor and aerobic membrane reactor


Duyar A., Ciftcioglu V., CIRIK K., CİVELEKOĞLU G., URUŞ S.

SCIENCE OF THE TOTAL ENVIRONMENT, cilt.776, 2021 (SCI İndekslerine Giren Dergi) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 776
  • Basım Tarihi: 2021
  • Doi Numarası: 10.1016/j.scitotenv.2021.145919
  • Dergi Adı: SCIENCE OF THE TOTAL ENVIRONMENT

Özet

Landfill leachate (LFL) is one of the most serious environmental problems due to the high concentrations of toxic and hazardous matters. Although several physical, chemical, methods have been tested, biological processes and single or multiple-stage combinations of them have been receiving more attention due to their cost-effective and environmentally-friendly manner. The present work recommended coupling of conventional single-stage A/O with moving bed biofilm reactor and membrane bioreactor (AnoxMBBR/AeMBR) for LFL treatment. The system performance was evaluated for 233 d under varying nitrate concentrations (100?1000 mgNO3?-N/L), sludge retention time (SRT) (30?90 d), and HRT (24?48 h) in AnoxMBBR, and constant SRT (infinite) and HRT (48 h) in the AeMBR. The best system performances were observed at 1000 mgNO3?-N/L concentration, SRT of 90 d and HRT of 48 h, and the average removal efficiencies of chemical oxygen demand (COD), ammonia nitrogen (NH4+-N), and nitrate?nitrogen (NO3?\\N) were 74.2%, 99.7%, and 89.1%, respectively. Besides, the AeMBR was achieved above 99% NH4+-N removal and not adversely affected by varying operation conditions of AnoxMBBR. A slight increase in selected phthalic acid ester (PAE) concentrations (diethyl phthalate (DEP), di (2-Ethylhexyl) phthalate (DEHP), diisononyl phthalate (DINP)) was detected in the AnoxMBR, and complete PAEs removal was attained in the AeMBR. Mg, Al, Si, Na, Fe was detected by SEM-EDX analyses in both biofilm of AnoxMBBR and the cake layers of AeMBR. Nitrobacter and Nitratireductor which showed a relatively high abundance played an important role in the removal of NH4+-N and COD in LFL. The results confirmed that the proposed sequence is efficient for COD removal, nitrogen removal, and PAEs being an acceptable treatment for landfill leachates.